TOSA Reference Model 0.80 Release

Conformance test repository is now deprecated, conformance test
generation scripts are in the reference model repository
Deprecated TensorFlow Lite based conformance tests
    Framework tests still generate TFL tests
Add support for new operators
    DIM operator for shape inference
    New unsigned attributes for RESCALE input and output
Improve TOSA flatbuffer compatibility checks
Fixes for test and reference model cleanup
Enable reading/writing native data types for numpy files
Various other cleanup, see the git revision history for complete details