Tools for Augmented Pure Python transition

The proposal is to facilitate bridging the gap between performance gains of Cython and coding readability and maintenance of Python

The rationale is that often a debugging activity stumbles upon a cython module that cannot be easily interacted with (add print, recompile, etc...). It is sometimes convenient to quickly change that cython into Pure Python

Another rationale is that it is often needed to reduce latency in some part of the code (looping over a oracle list of pairs, etc). Augmented Pure Python or Static Typing provide this benefit without compromising the ability to function in Pure Python mode by simply removing the compiled versions

This is NOT a change to HB code, but the addition of a convenient set of tools (change in setup.py and added clean_for_debug script) to navigate between the different modes of Python+Cython