Remove unused UIController methods.

Change-Id: I9843993403107bebb9f7506cf8adbb3410a2d780
Depends-On: I86a87f0b42ef36760d6188fd191de1dd8fdb92f3
Reviewed-on: http://gerrit.dmdirc.com/2905
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Build Manager