Fix some URLBuiler/IconManager usages.

Change-Id: I4c28424f377d992cf7e66f1f8586f9572a08a8a4
Depends-On: I78eb7366d28aeee08fce805218a4a29ce6ec4cb2
Reviewed-on: http://gerrit.dmdirc.com/2748
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>