* resolve -wall warnings with clang-8

* remove -Wno-extra-semi-stmt

* Unnused parameter cleanup

* style

* Fix CPU unused parameter warnings

* md used in mkldnn1.0

* latest PlaidML-GPU updates for 0.26

* Update Release Notes page for 0.26

* Add retry to clone step

* Increase checkout timeout

* Static linking refactorization

* File name changed

* Doc for PR 3497 - improve static backend apis

* Merge issue

Remove static initializers from ops

* Static linking refactorization

* File name changed

* Update changes.md

* Merge error

* revert

* Review comments

* WIP

* Fixes

* Increase bitwidth for arg idx attrib

* Minor fixes

* style-apply

* nGraph-ONNX CI improvement

- Added parallel CI on many SKUs,
- Jenkinsfile written in Declarative Pipeline which allows displaying sequential stages for parallel branches in Blue Ocean
- Moved proper CI code to ngraph-onnx repository
- Moved base_image_builder to ngraph-onnx repository

* Fix license header

* try catch for git info retrieval

* Add unsupported ops to iGPU backend

* Revert previous change

* [MLIR] Enable LIT testing in CMAKE

This PR enables LIT testing in nGraph for MLIR Compiler, introduced in
PR3523. We can now do `make check-mlir-lit` to run LIT tests.

* Address feedback

* Revisit PR after cmake clean-up

* [MLIR] Introduce ngraph-opt tool

To be used, among other things, for LIT testing.
`elementwise_binary_ops.mlir` shows a simple LIT test
using ngraph-opt.

Dummy affine_lowering/lit_test.mlir test that served as initial testing
of LIT tool configuration is now removed.

* Address feedback

* Bump MLIR version and minor fixes in nGraph

* advance commit ids

* fix commit id

Fix reshape error for onnx (on master)

Fixed NormalizeL2 decomposition for input shape length != 4

Initial support for float16 was done before the ngraph::float16 data
type was introduced in nGraph. This PR aligns ONNX frontend with the
latest float16 implementation.

* cleanup op includes in headers

* fix missing include

* [MLIR] Enable LIT testing in CMAKE

This PR enables LIT testing in nGraph for MLIR Compiler, introduced in
PR3523. We can now do `make check-mlir-lit` to run LIT tests.

* Address feedback

* Revisit PR after cmake clean-up

* Use mkl-dnn v1.0 or v0.x depending on compilation flag.

* Change cpu builder files.

* Modify cmake files.

Use mkldnn-v1.0 for DEX if NGRAPH_USE_MKLDNN_V1 is set to true, otherwise use mkldnn-v0.x.

CODEGEN only builds with mkldnn-v1.0.

* Implement mkldnn utility functions for mkldnn-v1.0.

User mode scratchpad management for mkldnn-v1.0.

* Query scratchpad size and allocate a buffer of max scratchpad size.

* Do not create mkldnn::memory when query scratchpad size of Reorder.

Modify mkldnn utility functions.

Fix convolution_forward_init and inner_product_forward_init.

Modify CPURuntimeContextCG.

* Add user mode scratchpad to CODEGEN.

* mkldnn-v1.0 splits LSTM states. Update Rnn/Lstm Op accordingly.

* Address PR feedback: use MKLDNN_MAJOR_VERSION.

* Modify cpu rnn fusion pass and related unit tests.

* Change Rnn/Lstm arg types to Output.

* Fix Lstm for CODEGEN.

* Set native layout for Slice when input format is blocked.

* Do not print scratchpad size.

* Change external_mkldnn_v1.cmake.

Fix a typo.

* Add mkldnn_v1.patch for mkldnn-v1.0.

* Address PR feedback.

* Define MKLDNN_ERROR_MESSAGE.

* Address PR feedback: change to NGRAPH_USE_LEGACY_MKLDNN.

* Fix a bug.

* Remove unused variable.

* Fix compiler warnings.

* Fix a bug for CODEGEN.

* Move variable only needed for mkldnn-v0.20 inside #if.

* Remove unused variables.

* No in place Reshape rotation for blocked data layout with mkldnn-v1.0.

* Modify mkldnn_v1.patch to force mkldnn to link to libiomp.

* Fix style.

* Change path for find_library and find_file.

* Do not insert ConvertLayout before/after Quantize/DeQuantize for blocked data layout.

* Write strides information to visualized graph.

* Move variables only needed for mkldnn-v0 under #if.

* Move more variables in rnn fusion.

* Fix ConvertLayout constant folding for mkldnn-v1.0.

* Add missing includes

* style

* Don't hold to shared pointers after sub-graph extraction pass is done

* style

* Add replace_by_friendly_name function

* Add replace_nodes function

* Nuke replace_by_friendly_name

* Modify replace_nodes to handle parameter replacement

* Move required reshape helpers to builders

* Remove warning from matmul_factory

* Rid off onnx dependency from matmul factory

* Move malmul_factory into builders

* Add implementation of fused MatMul

* Add MatMul to serializer

* Add type_prop tests

* Remove reference.

* Make more metods private

* Use protected instead of private

* Fix compilation issues

* Change construction of matmul_factory in matmul op

* Add MatMul operator into switch of is_supported_impl function

* Change transpose flags from int to bool

* Review Fix I

* Update MatMul op

* Use OutputVector instead of NodeVector in MatmulFactories

* Fix usage of OutputVector

* Convert more shared_ptrs to Outputs

* Fix comments after merge

* Fix comments after merge II

* Fix comments after merge III