Add some games

[illwieckz]

Add some games and edit some:

• DDRaceNetwork (Teeworlds derivative).
• Warfork and Cocain Diesel (Warsow forks).
• Rexuiz (Nexuiz fork).
• Remove TremFusion that was just an alternate client for Tremulous.
• Replace the Teeworlds masters by the remaining one that still works.
• Parse the Teeworlds game type.
• Use the official ET:Legacy icon.