Graphics and fixes
* switch to modern OpenGL with shaders
* implement preemptive asset data converter (oven)
* rewrite asset data loading
* add fallback data
* add piece models
* add textures
* add move/fire indicator
* add tooltips
* add audio system
* add window icon
* add hover events
* add loading log screen
* add custom cursor
* add icon select on click
* fix turn record indices
* fix FF indicator
* fix startup FF counter
* fix crash on popup close
* fix widget deselecting
* fix argument interpreter
* fix window positioning
* fix Windows directory separator checks
* fix scroll momentum
* fix memory leaks
* fix label text positioning
* remove unnecessary filesystem utilities
* remove text input checks
* change piece icons
* change font
* change materials
* change settings
* update readme
* update cmakelists
* refactor a bunch of stuff
