* Match build-windows.bat changes

The location for manual setting of the vcvarsall.bat location moved to line 38 in the latest change.

* Update flags for clean x64/x86 building

std:c11 is required for initialization features used in raylib.  UTF-8 for consistency in contemporary systems.  /W3 gets rid of puzzling slack byte and linker in-lining warnings.  /sdl for some insecure library usages in the user code that beginners should learn about early.

raylib modules have been slightly renamed to add some identity and note that they are independent modules that can be used as standalone separate parts of raylib if required.

The renamed modules are:
 - `core` -> `rcore`
 - `shapes` -> `rshapes`
 - `textures` -> `rtextures`
 - `text` -> `rtext`
 - `models` -> `rmodels`
 - `camera` -> `rcamera`
 - `gestures` -> `rgestures`
 - `core` -> `rcore`

All the build systems has been adapted to this change.

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.