Planning to promote raudio module as a simple and easy-to-use front-end for the amazing mini_al library, so the name change.

Name comes from raylib-audio but in spanish it also remembers to word "raudo", meaning  "very fast", an analogy that fits perfectly to the usefulness and performance of the library!

Consequently, raylib version has been bumped to 2.4-dev.

It was develop before, which is no longer used.

The link to rlgl in the README was broken, it previously pointed to a .c file which doesn't exist (anymore).

Fixes https://www.reddit.com/r/gamedev/comments/90z6fy/raylib_20_released/e2v5qpl/ :)