Moved the clips code to a clips subfolder in native.

This will make it easier to differentiate between clips code and scummvm engine
code.
Rewrote the module.mk file to reflect the change in the native folder layout
Updated the clips include paths for the platform code
Updated the include paths for the scummvm code
Merge branch 'master' of https://github.com/DrItanium/AdventureEngine-Scummvm