* Config for TF 2.0 Faster R-CNN models, refactored subgraph_between_nodes to use graph API
* Added support for new type of Preprocessing block in the TF 2.0 OD API models. Various fixes to enable the Faster R-CNN ResNet 50
* Updated text comments
* Fixed sub_graph_between_nodes for TensorIteratorMerge. Added support for the TF 2.X EfficientDet models (not yet reshape-able)
* Fixed unit tests
* Fixed regression for TF 1.X OD API SSD model, enabled TF 2.0 OD API SSD models
* Code clean up
* Switched TF 2.0 OD API Faster R-CNN to preprocessor replacement type 2
* Refactored ObjectDetectionAPIPreprocessorReplacement and ObjectDetectionAPIPreprocessor2Replacement
* Fixed bug in the Div transformation to Mul when input is integer.
* Added support for the TF 2.0 OD API Mask R-CNN
* Added unit tests for Div operation. Updated incorrectly modified mask_rcnn_support_api_v1.14.json
* Updated document with list of supported configuration files for TF OD API models
* Review comments
* Added tests for control flow edges for the sub_graph_between_nodes function
* Two more tests
* Removed back phase transformations related to IRv7
* Fixed setting value for the input port using the 'set_value' method
* Removed front and middle phase transformations related to IRv7
* Cleanup the rest of the Model Optimizer transformations from IRv7 specific transformations
* Final cleanup of the deprecated IR v7 related code
* Removed 'blobs_as_input' usage in the Model Optimizer.
* Removed function '_fuse_add' from the Model Optimizer since it is not used anymore.
* Removed 'keep_in_IR' node attribute for FakeQuantize ops in the MO
* Disabled failing gpu_engine.user_context test
Alexey Suhov