Add feature to load external font tags.

[Aerocatia]

HEK format font tags could be loaded form a fonts directory local to the executable.
Using libinvader the font tag would be compiled and then injected into the game overwriting the referenced fonts. Options would be configured in the ini. This could also allow us to potentially have high definition fonts without having to do nasty things to maps directly.

Example of options.

[font]
enable_external_fonts=1 ; enable or disable
system_font=interstate_large ; name of font tag(s) in fonts directory
system_font_scale=0.25 ;scale to render it. we could only use one global value if it turns out scaling individual fonts does not work.
console_font=interstate_mono
console_font_scale=0.25
large_font=interstate_large
large_font_scale=0.25
small_font=interstate_small
small_font_scale=0.25

Advantages:

• You can ensure you always have a monospace console
• Option to use HD fonts that look nicer and allowing feature parity with with DX injection mods.
• You can ensure chat, sever messages and scoreboards always look correct with your setup as fonts would always be consistent.

Disadvantages:

• We would be completely disregarding tag data currently in the map. this is gross.