Updated translation

Updated latest strings
Removed blinking grey area in the "Hidden movement" state;
Centered "Loading game" and "Saving game" messages;
don't need save _inDogfight flag
Merge pull request #617 from Xracer/patch-1

Updated translation
Merge pull request #620 from redv/interface6_hidden_movement

UI improvements: fix for wide screens
Merge pull request #622 from redv/fix_dogfight

Fix: Bug report #237 - Interceptor can never enter air combat again, when game was saved while in air combat
ruleset updated for proper wikipedia
Merge branch 'master' of https://github.com/SupSuper/OpenXcom.git into xracer-WIP1