* Concat operator is updated to support dynamic_shape
1) Added new concat_negative_indexing test
2) Replaced size_t -> int64_t
3) Support for a negative indexing, calculate axis = axis + int64(input_rank)
   if (axis < 0) { axis = axis + int64_t(this_input_rank); }

* Remove unwanted #include "ngraph/op/constant.hpp" header

* Refactoring:
1) The name of variable is replaced: m_concatenation_axis -> m_axis

* Concat negative indexing test is adjusted to support dynamic_shape tensor
auto pshape_a = PartialShape::dynamic(); for each tensor {a,b,c} result tensor has dynamic_shape

* The backend supports dynamic shapes
auto backend = runtime::Backend::create("${BACKEND_NAME}", true);

* Other shape is supported by concat:
set_output_type(0, inputs_et, PartialShape::dynamic(concatenation_axis_output_dim));

* The NODE_VALIDATION_CHECK was moved up to be for a dynamic_shape

* [Test] The shape of output tensor was changed
[Concat CPU] Added support for a negative indexing on a cpu

* Review changes:
1) Added axis re-calculate for a reference version of concat
2) axis is not replied

* Review changes: support for a negative axis

* Comment about variable is added to concat.hpp file
Removed unused variable

* Added auto generated configs for nGraph

* Fixed absolute paths

* Fixed comments

* Add constant folding for v1 reduce ops.

* Add reference/mean.hpp.

* Remove extra semicolon.

* Address PR feedback.

* Add constant folding for Squeeze and Unsqueeze.

* Address PR feedback.

* add partial slice op placeholder

* fprop implemented

* add a dynamic ut

* implement bprop

* support decrease axis

* add bprop ut

* address comment

* use descriptive var name

* Updated nGraph backend to be compatible with OpenVINO plugins

* Resolve issue with gtest

* Resolve comments in PR

* Resolve comments in PR

* Code style fix

* Rename runtime2 to ov_runtime

* Style check fix

* Dynshape support for GenerateMask

* fix clang error

* Remove comments

* Test case correction

* Disable plaidml

* Merge

* Added relative paths for python build

* Fixed Ninja generator

* Implemented downgrade pass

* Added v1 support in onnx importer

* Clang style applied

* Pooling factory refactor

* Removed unused variables

* clang styles apllied

* Fixed avg pool bprop UT

* [MLIR] Modify mlir subgraph extraction pass.

* Address PR feedback.

* Modify sub-graph construction algorithm.

* Address PR feedback.

* Address PR feedback.

* Change macro to function.

* Remove debug output

* More cleanup

* unfold attributes

* Remove unnecesary if

* Rename run() -> lstm_pass()

* Unify usage of LSTMForward for one and bi directional LSTM

* Unify LSTMForward return values for one and bi directional LSTM

* Dirty moving LSTMForward into fused directory

* Accept lstm direction as string instead of enum

* Fused op which uses decompose_op in onnx_importer

* Rename LSTMForward -> LSTMSequence

* Split LSTMSequence to cpp and hpp

* Remove LSTMDirection enum

* Add getters for class fields

* Adjust constructors

* Add direction validation.

* Add support of LSTMSequence op in serializer

* Reorder fused op input order

* Style fix

* Fix for reorder of inputs

* Use NodeTypeInfo instead of static string

* Node -> value in doc

* Add doc for prepare_input method

* Fix shape inference

* Use enum instead of string for direction

* Add Type prop unit test

* Fix style

* Check size requirement before creating scratchpad.

* Check max scratchpad size before allocating scratchpad_buffer.

* Add the same checks for CODEGEN.

* Fix unused-parameter warning.

* Fix a typo.

* Address PR feedback.

* Fix a bug.

* Fix style error.

* AvgPoolBprop dynamic shape support

* Add opset_transform test

* Call the correct shape relevance function

* Unused variable

* Support auto broadcast in FakeQuantize op

* style fix

* add pdpd unit test to plaidml manifest

* Make axis for TopK dynamic

* set_input_is_relevant_to_shape

* Proper handling of output shape with dynamic top_k_axis

* fix ut

* remove unused line

* check is_constant

* add v0 version

* update provenance

* use set_argument

* fix clang

* Minor cleanup

* Add support for ONNX 1.5 version of TopK

* Add unit tests

* Style apply

* Exclude failing tests

* Exclude failing tests

* Add support for ONNX 1.6 TopK attribures: larges and sorted

* Support for ONNX 1.6 TopK

* If k_node is a Constant, recreate as constant with Shape{}

* Extend `interpret_as_scalar` function

* Extend `interpret_as_scalar` function

* Remove merge artifact

* Add doc string

* Exclude failing tests

* Exclude failing tests

* Refactor function

* Remove unnecessary template param

* Use get_k function in OpSet 10 TopK

* Style apply

* Remove merge artifact

* Add tests for `interpret_as_scalar`

* Revert "Add tests for `interpret_as_scalar`"

This reverts commit 8b85965acb39c75ff9e66b06ad8f64df16e1a9da.

* - Added support for v1 Broadcast op specification
- Added upgrade/downgrade conversions between v0 and v1

* Added unit test for pdpd broadcast

* Make numpy default autobroadcast type and some style fixes

* Added support in Dynamic wrapper for dyn elimination and copied over unit tests from DynBroadcast

* Addressed PR feedback

* Addressed PR feedback on documentation

* Added a callback registration to the event class so that frameworks can decide how to write the events. Note: This is FULLY backwards compatible i.e., no change in the API so - won't break existing users

* Fixed compilation error

* Attempting to fix broken Windows build

* Fixed a race condition in the test

* Attempt to fix windows build again

* Create a variant schema and allow nodes to have a rt info

* Use map for rt_info

* style

* Another variant

* variant

* style

* Macro didn't work in gcc

* Compiler issues

* Skip shape inference for fused ops in the presence of dynamic-shaped inputs

* Added unit test to check fused op construction with dynamic input shapes

* Update changelog

* Title casing requested for documentation landpage

* Note new minimum version of Clang is 6

* Unify test names for opset transformation passes

* Unify downgrade test names

* [ONNX] Added Expand op to ONNX importer.

* Added support only for static broadcating.

* Changed version of set from 8 to 1.

* Added test for expand op.

* [Py] Added operators GroupConvolution and RNNCell to Pythpn API

* [Py] Removed code unrealated to branch.

* [Py] Undo removed test.

* [Py] Added removed decorator.

* [Py] Code formatting.

* [Py] Added ops to documentation's list.

* [Py] Added skipped file.

* [Py] Code formatting.

* [Py] Code formatting.

* Revert "Merge branch 'master' into etusien/GroupConv_RNNCell"

This reverts commit a1848ea48916b293d5260869b2a52827bea21981, reversing
changes made to 6a60068abf8e5391bf875ee22573eb1aa388b047.

* [Py] Reverted changes.

* [Py] Changed imports' list

* [Py] Added missed imports.

* [Py] Added operators GroupConvolution and RNNCell to Pythpn API

* [Py] Removed code unrealated to branch.

* [Py] Undo removed test.

* [Py] Added removed decorator.

* [Py] Added ops to documentation's list.

* [Py] Added skipped file.

* [Py] Code formatting.

* [Py] Code formatting.

* [Py] Reverted changes.

* Revert "Revert "Merge branch 'master' into etusien/GroupConv_RNNCell""

This reverts commit 9c46ce5d289dadc4979e4712c79fff84bb538652.

* [Py] Reverted changes.

* [Py] Code formatting.

* [Py] Code formatting.

* [Py] Added PadType to Group Conv op.

* make axes dynamic

* add ut

* update softmax deserializer

* check axes to be constant

* remove duplicates