SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Instead of selecting languages based on the user config at the time
of TitleDatabase creation and merging the different languages into one
map for GC and one map for Wii, have one map for each language, and
have the caller supply the language they want. This makes us not need
the IsGCTitle function, which is inaccurate for IDs that start with D.
The difference between Dolphin's game IDs and GameTDB's game IDs
is that GameTDB uses four characters for non-disc titles, whereas
Dolphin uses six characters for all titles.
This fixes:
- TitleDatabase considering Datel discs to be NHL Hitz 2002
- Gecko code downloading not working for discs with IDs starting with P
- Cover downloading mixing up discs with channels (e.g. Mario Kart Wii
and Mario Kart Channel) and making extra HTTP requests. (Android was
actually doing a better job at this than DolphinQt!)
The earlier code always tried to use TitleDatabase for getting
title names, but that didn't work for disc-based games, because
there was no way to get the maker ID.
