* update licenses for 2019

* style

* print llvm build choice and allow cmake arg to override env var

* fix cmake error

* use existing function

* Forward nGraph's C/C++ compiler, build type and generator information to cmake based external projects.

* Fix typo.

* Pass generator related info properly.

* Googletest is using DEBUG_POSTFIX

* TBB uses postfix for debug lib.

* Fix typo.

* Add GPUH hybrid backend

* update manifests

* update node operator<<

* fix GOE

* remove debug

* remove debug

* more cleanup

* add parent support to cpu and intel gpu backend tensors

* cleanup

* fix odd failure when printing node during construction

* fix node output

* address review comments

* style

* update build byproducts to support ninja

* remove unused cmake code

* more cmake cleanup

* display error message if Ninja generator is requested

* fix mkldnn ext project

* revert onnx cmake file

* revert protobuf cmake file

* revert mlsl cmake file

* more fixing

* add empty framework for hybrid GPU, or GPUH

* move placement to the runtime directory

* wip

* skeleton for hybrid GPU backend. most unit tests pass.

* cleanup

* move hybrid code into hybrid dir/namespace

* move hybrid functions

* move more hybrid functions to hybrid directory

* fix placement after compile. All unit tests passing

* fix gpu backend ctor

* files pulled from bob/winbuild

* fix compile problems

* fix a few windows build errors

* add windows file to exclude from git

* add comment why change was made

* revert obsolete change

* more cleanup

* building interpreter and unit test on windows with DLLs

* Add flag for windows to export all symbols. Short term fix.

* enable MD build

* address warnings

* dump all windows build results to a single directory

* fix windows backend dll open issue

* remove debug

* fix file iterator for windows

* fix merge error

* fix test failure

* change header from h to hpp in hopes of making python happy

* address more linux build issues

* fix visibility enable

* wip

* wip

* style check checking

* try cmake version of check/apply style

* update style check to print list of files in error

* cleanup

Use @loader_path for the calling library/executable
Use @rpath for dependent libraries.

* remove version tagging from shared libraries

* add flag to enable/disable library versioning

* disable in-tree build

* check to prevent in-tree builds

* [Py] Add make python_wheel target

* Add make install step

* Use tagged pybind11 version 2.2.4

* build seems to work

* cleanup

* add backsuport for using pre-built clDNN library

* fix typo

* more sdl changes

* more fixes

* update SDL

* cleanup

* cleanup

* rename var

* redo how in_transition is handled

* add -O2 flag back

* fix gtest abi build

* fix llvm build with abi flag

* remove debug

* add check for conflicting flags in cmake

* add nop backend

* nop backend

* fix flag name

* add new switch to cmake output of switch settings

* add new unit test to igpu manifest

* remove redundant test

* address issues which surface with clang 6.0

* revert changes due to new clang warning and disable new warning

* wip

* wip

* wip

* move hybrid wrapper to hybrid backend dir

* move hybrid wrapper to correct namespace

* wip

* sorta working

* remove debug from sorta working homogeneous hybrid backend

* is_supported is supported for GPU

* cleanup debug

* more progress

* remove debug

* cleanup

* turn off hybrid by default

* revert change

* revert

* rename wrapper to backend

* revert

* address review comments

* style

* 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

* Move to TBB2019 and bug fix to capture functor

* Change to use TBB release tag

* remove lightweight from codegen

* Enable TBB flow graph tracing

* skeleton backend

* Code owner from if conditioning

* add simple placement for interpreter and register pass in hybrid

* placement policy applied

* clone the function if needed

* split the function

* Compile subfunctions in corresponding backends

* hybrid backed works as is for abc test

* cleanup

* add placement policy for CPU

* cleanup a little

* add simple op cost method to backend

* enable CPU pass via flag

* address clang-format PR issue

* reslove build

* clean-up

* update manifest

* disable HYBRID as default build

* style

* addressing offline discussion

* more offline discussion

* move backend specific test files to test/backend directory

* remove unit_test_control

* move tests back to test root

* fix comment

* wip

* fix manifest

* Added cmake flags to specify D_GLIBCXX_USE_CXX11_ABI and disable building of doc

* Renamed the NGRAPH_DOC_BUILD_ENABLE flag based on PR feedback

* cmake: use GNUInstallDirs to autodetect installation directories (Linux)
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* define LINUX variable to detect Linux
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnxifi: add 'onnx' as external project
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnxifi: public interface function stubs
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnxifi: fix the typo in function name
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnx: fix compilation Ubuntu 16.04
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnxifi: update to dummy backend
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnxifi: style cleanup
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* add detection of Linux distribution
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnx: disable ONNX unit-tests if CentOS detected (temporar solution)
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* onnx: correct DISTRIB_ID name for CentOS
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>

* Optionally get rid of codegen from the CPU backend

* Rename option variable

* Merge fixes

* Merge

* Remove extra changes

* remove dex only exclusions (#1429)

* Unconditionally pick  m_direct_execution if NGRAPH_DEX_ONLY

* Style fix