Changes

• Fix not showing an error when per-game plugin settings are invalid
• Fix settings dialog behavior for plugins not being the same for per-game plugin settings
• Add 'restore defaults' button to configuration GUI of paraLLEl and angrylion-rdp-plus
• Add 'OpenGL type' option to the settings dialog which allows choosing OpenGL ES
• Add dynamic OpenGL ES detection to angrylion-rdp-plus (see ata4/angrylion-rdp-plus#157)
• Improve screen size selection by making it editable in the configuration GUI of paraLLEl and angrylion-rdp-plus
• Improve letter casing in settings dialog, RMG-Input and RMG-Audio
• Improve about dialog
• Change 'Miscellaneous' tab name to 'General' and change position in settings dialog
• Update GLideN64 and SDL_GameControllerDB