* Reference tests via OpenVINO 2.0
* Migrated to new API acos test
* Fixed other tests compilation
* Fixed tests
* Reference tests use ov::
* Fixed compilation
* update spec, init backend file for equal op
* add backend, visitors, serialize SLT tests
* add backend test to manifest cause of mismatch of output type with cpu plugin
* add equal to list of trusted ops and to cmakelist file
* refactor backend tests to the new template
* refactor spec
* remove external link in numpy broadcast and update example
* remove comparison.in.cpp file and related tests from manifest
* fix example
* remove redundant arguments
* refactor backend tests
* add pdpd broadcast to the spec, and different precison to SLT test
* add precisions to SLT cpu
* remove unsupported type from SLT
* revert the deletion of comparison.in.cpp file
* remove visitors test, since it will be added in the other PR
* remove equal from CMakeLists.txt
* refactor links in the spec
* revert unwanted changes
* remove equal from unit test manifest
* revert links modification in spec
* add namespace
* split SSLTs for comaprison ops into seperate files
* fix SSLTs names
* add missing new lines
* udpate output type in spec
* rafactor numeric backend test to template
* merge numeric template tests into equal
* Revise spec
* Comparison backend test POC
* Split Comparison ops tests into separate files
* remove comparison.cpp, remove unused imports, replace for_each with range based for
* remove unnecessary ngraph:: prefixes
* Fix links in spec
* Add Less to trusted ops list
* Add missing ','
* Use builder in backend tests
* Remove old backend tests for less, equal
Alexey Suhov