Added several optimized options for future reference (if required)

Co-authored-by: frithrah <simon@frithrah.com>

Some resources used in examples have not a clear license, so, I'm replacing some of them for clearly licensed versions or resources created by me under CC0. License file to be added.

Co-authored-by: Branlix 3000 <branlix@3000.3k>

- The Mouse struct already stores cursorOnScreen. This function simply exposes it to the usage code.

It could be useful in a future...

Switched custom WAV laoding/saving funtionality to drwav library, it also provides the required mechanisms to stream wav data.

Compression API requires functions provided by stbi_image_write (DEFLATE compression)

This change could introduce an issue on dataSize precalculation...

All functions requiring sizeof() now follow the same convention:

NUM_ELEMENTS*NUM_SUBELEMENTS*sizeof()

Several functions used to load external files have been reviewed to just load the full file with LoadFileData() and load data from memory from there. This way all file access functionality is centralized in utils module.

Functions reviewed: LoadDDS(), LoadPKM(), LoadKTX(), LoadPVR(), LoadASTC(), SaveKTX()

* added BLEND_SET

* renamed BLEND_SET to BLEND_ADD_COLORS