There was confusion in the lighting code between light indexes and sun indexes. These are usually the same, but not always. This makes several changes to fix light/sun handling.
1. Clarify the distinction between lights and suns and add a `sun_index` field
2. Add a flags field and assign the `dual_cone` boolean to it, as well as a new glare flag
3. Determine light glare by checking the light flag, not the sun (which never worked in the first place as the `stars_sun_has_glare` function checked bitmaps rather than suns)
* Create the ingame options game state
* Base working version of in-game options
* Cleanup + Optimization
* Localization pass
* more cleanup + documentation
* tooltips on option hover
* documentation and better inbounds check
* match case
* format strings instead of direct strings
* unused parameter
* address feedback
* localization id conflict with master
* Add this line back in
* pass the new option flags as well
* resolve xstr id conflict
* Reorganized opengl deferred light mesh drawing to submit all data before,
beginning to submit draws, and also to reduce total bind calls needed.
* Leftover unused variable cleanup
* CI didn't like my loops, maybe it'll like these.
* unused variable cleanup.
* SCPUI in-game language selector
* xstr support
* proper debug print format
* minor fixes
* Save the language as json data rather than an index into the languages array
* ext instead of id for clarity
* Do this more formally
* unused param
Convert additional timestamps to use the new timestamp system. This covers all timestamps referred to in freespace.cpp. For purposes of organization, the fade-in/fade-out timestamps have been moved to light.h|cpp and the training timestamps have been moved to missiontraining.h|cpp.
There are also several related code enhancements:
1. `FadeType` has been converted from `enum` to `enum class`
2. Initialization of the various training variables has been added to `training_mission_init` (previously they had never been reset between missions)
3. Validity checks have been added to the relevant locations for these timestamps
Goober5000