Added a bunch of useful text management functions.
Consequently, some already available functions like `FormatText()` and `SubText()` has been renamed for consistency. Created temporal fallbacks for old names.
raylib version bumped to 2.3.

Changed parameters order for consistency with LoadFontData() and other functions when an array is passed by parameter and array size is the following parameter.

raylib resource data file for Windows platform (containing raylib icon and metadata for executable file) has been renamed to a more consistent name: raylib.rc.data

Also required to work with tcc compiler.

* changed bitwise & to logical &&
* removed redundant state check
* moved a strcpy inside a NULL check to prevent a crash.
  NOTE: nothing sensible will happen as a result, but no crash at least.

Currently, if:
* GCC doesn't supports -no-pie: Build error
* GCC supports -no-pie
    * GCC is not configured with --enable-default-pie: No-op
    * GCC is configured with --enable-default-pie:
            Slightly worse performance because we still generate -fpie code
            (-pie affects linker, -fpie affects compiler)

So instead of probing for existence of -fno-pie -no-pie, remove it altogether.

Fixes #540: Build breakage on Debian 8 with gcc 4.9.

- Preparing MP3 files support
- Jumped version to raylib 2.0-dev (too many breaking changes...)

Removed OpenAL and GLFW3 dependencies on building.
Reviewed platforms and flags

Inspired by #504.
Instead of requiring the user to do PLATFORM_ANDROID #ifdefery,
have the android_main entry point exported by raylib and call
the user-defined main. This way many games could (in theory)
run unmodified on Android and elsewhere.

This is untested!

Supported UTF8 range equivalent to [128..255] (80h..FFh)
Exposed and renamed text function GetGlyphIndex()
Renamed spriteFont parameter name to simply font
Small security check on transmission mission ending screen

Support string replacing to generate newspaper headline
ISSUE: UTF8 characters not supported when drawing to Image

Game developed in the GGJ18, it has some bugs and ending screen is
incomplete... I'll try to keep working a bit more on it.