minimal changes for compatibility with lua 5.2, thanks to v4hn for fixing standard library loads. note: ALSO compatibile with (internal) lua 5.1, until something bothers to upgrade bundled lua version
07f3bf8d98a3
Hedgewars.png had a resolution more than twice as high as required; also fixed some (mostly obsolete) code that also contained a typo that would cause a warning/note in clang
