Mostly just cleanup and renaming of certain stuff (mostly in dependencies).
* Changed uw and sw to usize and ssize.
* Removed zpl_cast usage throughout dependencies
* No longer using GEN_DEF_INLINE & GEN_IMPL_INLINE
* header_start.hpp renamed to platform.hpp for depdendencies header.
Also now doing comment serialization on def_comment directly as parse_comment doesn't need it.
Essentially comment ast types serialize the same way s untyped and execution ASTs
This isn't the last step though everything in the main project directory that isn't md files needs to be generated only.
Can't do that till testing is robust enough...
