Add support for iPhone 5 resolution in-game
Adding very basic support for iPhone 5 for the in-game portions. The game now renders at 1136x640 for iPhone 5. Note: a placeholder iPhone 5 launch image was added because this seems to be required to get the game to boot into the new resolution.

Some things that need to be fixed on iPhone 5:
(1) The hud is stretched. I think it should be centred rather than stretched.
(2) The movement reticule is sized wrong. Appears to be rendering at the non-retina content factor scale.
(3) The menus haven't been fixed yet for iPhone 5. They don't properly centre on the new resolution.

Some other smaller changes in this change list:
Removed portrait from the list of supported orientations in the app .plist.