* Simplified & tightened all_close_f parameters

Removed specification of mantissa bits for all_close_f in favor
of just specifying tolerance bits. Tightened up all_close_f default.
Fixed LRN unit test which had insufficient result precision to pass
tighter all_close_f tolerance.

* Addressed PR comments.

Reworked mantissa bit and tolerance constants.
Clarified and improved graph comparison tolerance calculation flexibility.
Clarified unit test tolerance testing.

* update licenses for 2019

* style

all_close_f error reporting clarification. all_close_f test cases spaced out for easier interpretation. (#2247)

* Simplified all_close_f tolerance determination. Made all_close_f less verbose. Transitioned graph comparison to use double comparison when appropriate.

* Reworked all_close_f AssertionResult returning code to include message in AssertionResult on success also.

* Added CMake option NGRAPH_GTEST_INFO, which controls whether or not any gtest info cout is done. Quiets all_close_f tests by default.

* Moved NGRAPH_GTEST_INFO from build option to environment variable.

* change all_close tests to return gtest AssertionResult instead of bool to allow for better error messages

* change throw to return error

* address PR comments and fix compile error

* Double support for all_close_f

* all_close_f uses fixed number of mantissa bits now. Simplified testing code.

* Initialize test data members in constructor to values which will cause test failure. Setup then sets them correctly.

* Reduce info printed out during all_close_f unit tests.

* add some helper function

* update with new helper function

* update reduce to nd with new helper function

* update float sum to stable sum

* fix bug

* update all reduce to stable sum for float

* fix bug and pass the sum stable test

* remove debug info

* style

* update with shape

* fix bug

* add host parameters to cuda_emitter

* clang format

* fix bugs

* add element::type support

* format

* add a cached value with datatype name

* add init_reduce_value

* unroll loop

* optimization

* remove the need for init_value

* add memset kernel

* add memcpy

* working version

* remove debug info

* add comments, clean up code.

* change in_idx to input_idx

* fix bug

* change args name for memset in emitter

* pass element::Type instead of string

* the op::reduce come with init value, add support

* resolve codacy-bot comment

* fix bug

* resove codacy-bot comment

* remove unused comments, resolve comments

* cuda reduce for max, min, mul, reduce op init value, format

* use type::info

* use type info for numeric_limits

* remove code from gpu_host_parameters

* header

* remvoe outdated comments

* add helper to check if stable sum is needed

* add stable sum test for double

* remove extra line

* consolidate helper functions

* no need list now.

* remove extra ;

* clang format

* style

* add skip test for cpu and intelGPU side

* add line between groups of headers

* add two simple stable sum test for float and double

* skip test for intelGPU

* Additional info calculated & printed for all_close_f.

* Fixed format

* Tweaked test calls to all_close_f to make unambiguous.

* Tweaked test calls to all_close_f to match close_f for last unit test.

* add isfinite check

* style

* output 5 diff and total diff

* output limit of diff for all_close_f

* dix bug

* disable tests

* remove failing unit test that does not make sense.

* Heterogenous sub-graph comparison testing

* Print index for float differences

* Disabled compare_backends_with_graphs on most backends for now. Moved to new file. Added testing of unsigned values.

* Fixed element::boolean range. Added missing include.

* Switched use of shared_ptr as parm to raw *. Moved to using namespace std in cpp. Fixed comment marker in unit_test.manifest files. Switched some EXPECT_EQ TO ASSERT_EQ. Fixed parameterized test disabling.

* Frozen naming -> serialized. Removed extraneous comments.

* Graph comparison unit test relies on CPU for reference, so only build when CPU is built.

* Reworked per backend disabling of compare_backends_with_graphs

* rename files

* rename runtime TensorView to Tensor

* rename HostTensorView to HostTensor

* Remove "view"
Simplify layout

* Fix merge error

* fix build error

* PR1602. IntelGPU backend. Compilation fixed.

* use line comments instead of multiline comments for license header

* update more

* update new files

* more header updates

* style