Settings screen improvements

[seji1]

This pr:

• Cleans up some code
• Adds all fields for translations (Uses vanilla fields, where possible, so no need to translate options, that are already translated in vanilla).
• Makes gui scale a slider
• Adds icon instead of "Video settings" text
• Moves some settings into more sensible places
• Fixes Unique opaque layer tooltip (thanks to thr)
• Fixes a bug, where max possible gui scale was unavailable
• Fixes a bug, where RangeOptionWidget played click sound when control is not hovered

Some screenshots with LOLCAT language (Vanilla fields are used and my test translation ones too):

Only vanilla fields, no translation:

[seji1]

Resolves #181