Added missing options and rearranged the way they appear under legacy layout plus minor fixes:
* Added some default values after `=`
* Commented out options with default values
* Unified style
`gl_size_query = viewport` - specify what to use for getting display size. Options are "viewport", "scissorbox" or disabled. Defaults to using glXQueryDrawable.
`gl_bind_framebuffer = 0` - (re)bind given framebuffer before MangoHud gets drawn. Helps with Crusader Kings 3.
`gl_dont_flip = 1` - don't swap origin if using GL_UPPER_LEFT. Helps with Ryujinx.
* Added (commented out `fps_sampling_period`, `version` and `engine_version`)
* Commented out `legacy_layout` by default and added `=false` if one want to enable new layout
* Unified VSync, FPS, RAM and other minor names while at it
* Added space after comments sign for options that were missing it to unify formatting
* To save some memory, use just 1-channel alpha-only textures
* Add some sort of wider glyph ranges support
* Chop single-ish vulkan font image uploading function into separate reusable helper functions
* Use descriptor set for ImTextureID but probably use texture array and push constants for "fast-path" if need arises
* Crosshair is gone as of 0.4.0
* Changed keybindings to the default ones as of 0.4.0
* Added `gpu_name`, `cpu_text`, `gpu_text`, `gpu_power` and `vulkan_driver` in respective sections