_loadTabMenu doesn't use createUI

[l0rb]

_loadTabMenu creates new FlxUI objects for the contents of the tabs, but doesn't use a call to createUI to make them and instead directly instantiates FlxUI objects. This makes it very hard to use a customized subclass of FlxUI together with tab_menu.

[l0rb]

Notably, this issue has a fix in the lars_latest branch.