V7 Beta 7 - Acrylic effects!

Addtions:

• Backend for grabbing assets in the rich presence (Right now it's only used for the MultiRPC page)
• Finished up Installed Theme page and it's logic
• Settings being "Editable"
• Acrylic/Mica effect :D
• Warning for buttons not being clickable
• Migration logic in place (Not used yet)
• Directory check for filename not using correct variable which means it'll pass filenames that shouldn't be used
• Update Presence button now disables if the current rpc page is not what started the rpc connection
• Being able to remember what official theming the user selects
• Button Warning when the user adds a warning for the first time
• Disable/Enable Update Presence button based on the active rpc page on screen
• Use SemanticVersion for theming

Fixes:

• Theming not being applied correctly
• ThemePreview not updating the button colour
• Deleting whole theme file when we should override files (Being of assets possibly being in the theming)
• Crashing on Linux