[rtext] Font files `.fnt` can only be loaded by `LoadFont()`, not with `LoadFontEx()` and `LoadFontFromMemory()`

[Farbs]

Issue description

I was trying to load BMFont / Angelcode .fnt files using LoadFontEx, however it silently failed and returned the default font. Looking at the code for LoadFontEx, it seems that neither it nor LoadFontFromMemory have a pathway through to LoadBMFont, and that only LoadFont supports it.

I've added a note to the Using BMFonts page in the wiki in case it saves anyone else a bit of time.

Environment

Desktop, Windows 10, OpenGL 3.3, GTX1060

Code Example

Font doesNotWork = LoadFontEx("example.fnt", 32, NULL, 0);
Font works = LoadFont("example.fnt");

[raysan5]

@Farbs Good catch! Thanks for reporting! I imagine I just ignored that format because it is not the most common use case and LoadFontEx() is intended for a codepoint list request, while .fnt has already a codepoint list defined that user can not change... Still, it can be improved...

[CrackedPixel]

@raysan5 i was going to take a crack at this, but fnt files have separate files for resources. N amount, so its not a simple solution and raylib doesnt currently have a pattern for reading multiple files from memory

i made a PR to add a warning but i think this cant be pursued further until there is a standard pattern in raylib