* Initial implementation of GroupConv+BatchNorm fusion

* Added GroupConv+BatchNorm with Relu fusion

* Added changes to fuse with BoundedRelu

* Changed BoundedRelu to Relu

* Added test; Code cleanup

* Code formatting

* Removed dead code

* Added test cases and other misc

* Bug fix in group conv callback and general cleanup

* Address PR feedback

* Minor edit to comment. MKLDNN divides both input and output channels by groups

* Style fixes and PR feedback

* Add ArgMin operator

* Add ArgMax and a basic test case

* Rename variables

* Apply workaround for problems with Reshape on i64

* Review comments

* Review comments

* wip

* wip

* simple hybrid test harness

* cleanup

* disable unit test in progress

* Add PlaidML backend

* CR comments

Used m_ prefix for members; removed trailing underscores
Updated license headers
Moved associated header inclusions to project blocks
Wrapped comments to 100 chars
Added missing newlines between functions
Removed nested namespaces in operation implementations

* Add earhart to CODEOWNERS

* Rebase updates

* style

* fresh commit for the changes

* Working topk on ndims for nvGPU

* fix

* clang

* Added unit test, improved kernel hash and Bob's comment

* int64 test+clang

* Moved argReduce and topk tests to a separate file

* TopK unsupported for IntelGPU

* addressed Fenglei and Chris's comments

* addressed Fenglei and Chris's comments

* IntelGPU backend: Profile data improved

* PR1932. Comments addressed

* Move to TBB2019 and bug fix to capture functor

* Change to use TBB release tag

* remove lightweight from codegen

* Enable TBB flow graph tracing

* add split concat

* fix bug

* fix bug

* fix bug

* add test

* fix test bug

* add comments

* format

* return intead of check processed

* remove .back() since it's not vector anymore.

* format

* change to paramter tests based on Geoff's comments

* types-> type

* change split size to 256

* Reenabled Chris's nvcc building. Improved support for build paths and variations of cuda 8/9 + clang/gcc

* Improved build messages based on feedback

* Add builder for {de}quantize

* Add declaration in header

* Add mkldnn support for {de}quantize

* Add support for {de}quantize with mkldnn

* Add Dex support

* Generalizing some api's and adding a test case for DQ in backend_test.in.cpp

* Unify scale between ngraph and mkldnn

* Check for nullptrs

* PR feedback

* fix unit test failure

* Adding tests for builder and deleting the backend tests

* curly braces

* test rename

* gdb-like interface + tests

* fix not being able to run call twice without call

* fix continue bug

* fix enables; rename kontinue to resume

* switch from lists of functors,enables to vector

* address scott's feedback

* adding a debugger object

* address jayarams feedback

Add in place concat optimization.

Merge branch 'ayzhuang/in-place-concat' of https://github.com/NervanaSystems/ngraph into ayzhuang/in-place-concat

* m_direct_execution is used but not defined when NGRAPH_DEX_ONLY=TRUE

* keep the ifdef and move m_direct_execution out of the ifdef

Merge branch 'ayzhuang/in-place-concat' of https://github.com/NervanaSystems/ngraph into ayzhuang/in-place-concat