ZKL: Add UnitSync dialog box.

UnitSync dialog box is OFF by default. It allow ZKL to read new map/mod file without being connected to server & allow user to choose not to register new map/mod with server.

This will generally work. I would use it if I have no internet & want to tweak some mod


Also
1 unrelated commit https://github.com/xponen/Zero-K-Infrastructure/commit/08b42718ace2bca8cc6fcfb7f3d4660b89bd1578 to fix small UI bug, which is minor & not need another branch (I think). Wanted easy merge together