Support for 5D3 firmwares 1.2.3 and 1.1.3 in the same source tree
Looks like we should support both firmwares: 1.1.3 for general purpose and 1.2.3 for certain users (those with external monitors and those with f/8 lenses). Rationale: http://www.magiclantern.fm/forum/index.php?topic=14704
I would postpone the upgrade to 1.3.3 a bit. It will replace 1.2.3, but I think 1.1.3 is here to stay (so we'll have to support 1.1.3 and 1.3.3).
This PR attempts to support both firmware versions in the same source tree.