New Audio Edit Buffer Object / Click Removal /  ....

Multiple changes.

- new audio edit buffer object with zero crossing and linear fade
- click removal from downloaded audio resources in sound.h/.cpp
- consistent use of uint32_t & float32_t throughout all new audio objects
- most audio objects now have out-of-line inline members for updated coding standard
- loop unrolling for the performance critical audio-buffer object when scaling from int16_t and float32_t

Doesn't block the merge, I'm just curious: what is the motivation to use "float32_t" instead of just "float"?  I'm wondering if I should be using float32_t in my own code going forward.