Patch Set 6: I would prefer that you didn't submit this

this looks much better :-)

though there is still room for some improvements:
- list of repositories should be sorted
- when selecting destination using mouse the "Finish" button is only
 activated when moving the focus away from the combo I just used to
 select the destination. Hence I either have to click another combo which
will set another destination I might not want or I have to click the
checkbox twice or hit "Tab" key. I think instead "Finish" button should
be enabled when at least one destination combo has a selected ref.
- I couldn't find a way to set the destination without using the mouse
this should be also possible using keyboard