Rework of No Gravity script: - Now called Gravity, gravity is derived from get away time percentage in game scheme - Watchdog which sets gravity to normal when TurnTimeLeft is frozen for more than 15 seconds

file(GLOB luafiles *.lua)
file(GLOB cfgfiles *.cfg)

install(FILES
    ${luafiles}
    ${cfgfiles}
    DESTINATION ${SHAREPATH}Data/Scripts/Multiplayer)