Instance Segmentation Update

[Mruzik1]

• Added a class for exporting YoloV5 instance segmentation model.
  • Inherits from YoloV5Exporter, overrides load_model and export_onnx, has a new method prune_model.
• Updated the Exporter class.
  • Added a few changes to check what type of model we are exporting (methods get_onnx and export_openvino). Using the name is maybe not the best way to check the type. Although it has its own pros, plus we don't need to import anything that could affect flexibility of Exporter.
  • Changed quotation marks (' -> ") in the openvino command, because I had an error with those.
• Added a little script test_seg_export.py + folder model_files for generated files to test the changes.

[tersekmatija]

Thanks! Let's get the #57 merged in first, then rebase and review @HonzaCuhel . In the meantime, let's get the ONNX and blobs shared internally so we can start integrating protos into the FW @Mruzik1 .

[HonzaCuhel]

Sure! I want to first update the automatic version detection and then I'll merge it and deploy it. Is that okay, @tersekmatija ? Or should I merge the #57 now?