Main: Slight refactoring.
Squashed 'externals/SkipIfZeroCommon/' changes from 0bbfce7..dace353

dace353 Warning fix: Removed weird unicode character that looked like whitespace.

git-subtree-dir: externals/SkipIfZeroCommon
git-subtree-split: dace35392fe3685a2bbc1e16d329b6777c62c7c5
Merge commit '6b5d2d87b9f60ec81ac1ed812bb837f0fe072234' into development
Rather major rewrite. Now has a new enhanced 3d direction enum which it's possible to map 2d direction enums onto.