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Fixed Group identification of Air Force pilotsFixes#669.

Few minor fixed related to flatpak prepare

Make 2.0.0rc2 tagSet version in CMake 3.x style. We need that version anyway for C++11standard.

First 2.0.0 release candidateFixes failing builds on 32 bit platforms. Makes compatible games overnetwork.

Include build version in gameFixes several string formatting errors.Update icons and help.

Version 2.0 prepare, show version in-gameVersion did not show in game anywhere. Include it in credits.

Upgrade version information to 2.0.0Keep this version as alpha yet.Add make tag target to simplify tagging of new versions.

Old sources imported from 1.1 archive

Old sources imported from 1.0 release archive