MFH: r452072

games/openra: update to 20171014

• Drop DOCS as Lua API docs aren't available anymore
• Drop ZENITY as it's only used to show FAQ link on crashes
• Move game data to DATADIR, better mimicking hier(7)

Changes: https://github.com/OpenRA/OpenRA/wiki/Changelog#release-20171014
Approved by: ports-secteam (swills)