Tidy up NSD

Change-Id: Id140841e3bfaf01b72e4b0fe55741f86a071c87a
Reviewed-on: http://gerrit.dmdirc.com/2804
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Chris Smith <chris@dmdirc.com>
Fix dialog key listener.

Change-Id: I1fd06117a6484089aceaa0c56f186720fb5c94ff
Fixes-Issue: CLIENT-407
Reviewed-on: http://gerrit.dmdirc.com/2805
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Chris Smith <chris@dmdirc.com>