A few inspired things

This is in response to http://superuser.com/questions/743170/how-can-i-concatenate-multiple-clipboard-selections-in-quicksilver

Also tried to fix a few warnings, but given that there's an interesting note in `NSPanel.h` about it being deprecated, I stopped. We have `QSAlertManager`, and I was wondering if we could move our alert-building methods there (it's painful to allocate and set up in the Apple-sanctioned way now), as well as our Notification Center stuff (I have a feeling some things like the update system alerts would be better as notifications). Opinions ?