This allows more consistency in the manner we include core headers,
where previously there would be a mix of absolute, relative and
include path-dependent includes.
-Project/Editor settings now show tooltips properly
-Settings thar require restart now will show a restart warning
-Video driver is now visible all the time, can be changed easily
-Added function to request current video driver
When a phone call or an alarm triggers on iOS, the application receives
an "audio interruption" and it's up to the application to resume
playback when the interruption ends. I added handling for audio
interruptions same as if the game is focused out and then back in.
Using `misc/scripts/fix_headers.py` on all Godot files.
Some missing header guards were added, and the header inclusion order
was fixed in the Bullet module.
