Cleanup: Deletion of Nupic dead code

This is a PR that aims to remove dead code from NuPIC, i.e. code that is not used in any part of NuPIC. resources folder, for example, represents a large portion of the repository size but many of their files aren't used anywhere. This dead code could is making the cloning/download take more time than the necessary in addition to hinder the repository maintenance.

Please, don't review yet: I'm testing what could be removed without problems.