Homebrew now uses lua 5.2 by default.

Explicitly require lua 5.1.
Merge branch 'release_30' into release_31

Homebrew now uses lua 5.2 by default.
Switch to using QPointer for the debug console.
Use QPointer for all of the pointers to Host in other types.
Fix memory leaks related to the debug window.
Fix TEvent handling so it doesn't crash anymore.