Refactored plugin redating code.
Refactored old report reading code.
Removed some dead code.
Moved most of the generators code into a cpp file.

Since it doesn't use templates, it doesn't need to be in the header.
Removed unnecessary game reference variable.
Added plugin hashset, metadata lists to Game class.
Some mostly backend changes.

Metadata editor now lists plugins in their load order though.
Fixed wrong default repository branch.
Fixed settings being initialised incorrectly.

If the settings file was missing.
Fixed game reference causing overwritten settings.

Not the neatest fix, but the UI stuff is all going to change anyway.
Fixed build issues if parameters undefined.
Updated contributing and credits info.

Now gives prominence to GitHub forks as a contribution method.
Updated README.
Moved some #includes.
Updated language support instructions.
Changed misleading variable name.
Removed some unnecessary #includes.
Fixed typos.
Fixed libloadorder errors missing details.
Removed unnecessary log message.