Add FlatRedBall Engine

[MichaelHinrichs]

SteamDB app page links to a few games using this

• WeeRPG
• BattleCrypt Bombers
• The Incredible Baron
• Masteroid
• KosmoSquad
• King Randall's Party
• A.R.E.S. Extinction Agenda EX

Brief explanation of the change

Find files in root folder that begin with "FlatRedBall".

[SteamDB-Tracker]

After running changed rules in this pull request (this bot only tests rules.ini changes):

Changed technologies: Engine.FlatRedBall

These apps now match: (13) 92300 92310 236490 241500 315340 441510 814560 921450 1148320 1448070 1586330 1875240 2188930

Please confirm that all these changed apps are correct.

[Lifeismana]

merged in 1a64e318b4fcf174d5c9aae68119ca88270b0fa2