Add Module
Add CoreCallbackHandler
Rename SetCallback into CallbackSetter
Rename retro-core-global in retro-core-cb-data
retro-core-cb-data: Ported to C11
Make a config file at compile time

The config file contains the PREFIX
Core: Make a property out of get_region()
Core: Make a property out of get_system_info()
Core: Make a property out of api_version()
Use dark theme
Changed OptionsDialog for OptionsGrid and a Popover
Window: set default size to 800x600
Window: start game when loaded
Show display on game running