Fix spelling mistake in supplimentalKidMenuItems

Split out from #1410, this is somewhat of a breaking change. Most Loc subclasses outside of the Lift codebase will simply need a recompile. A subclass that overrides supplimentalKidMenuItems will not compile (it's now final, besides deprecated), requiring the overriding method to be renamed as well.
Ideally this would be included in 2.6, and 3.0 would only have the correctly spelled method.