Add skeleton and default Python implementation for additional layers

[Gaudeval]

Supported layers are limited, for a good reason, to those for which a code generator exists. It would be interesting to at least provide a Python implementation and specification for additional layer types.

A good candidate or reference specification would be the NNEF and oneDNN ones which provide clear specifications of the computations.

• List layers of interest
• Focus should be on the feed forward and parameters are required
• Code generation with those layers should fail.
• Importer support can be added later

[Gaudeval]

Obsolete, a lot of layers have been added by @yaitaissa while working on importers.