Allow tabbing on aas when alignment panel is open

[Susume]

It would be very helpful if we could tab over a segment while the alignment panel is open, to see how it is scoring, and what aa it is (I'm sure I'm not the only one who can't remember the one-letter abbreviations given in the alignment panel). When we move a segment along the thread it would be nice to see its score change and decide if the move is a good idea.

[Susume]

Silly me; I just discovered that the alignment panel will tell you what the letters stand for if you hover over them. I'd still like to see the segment score in the tab window, though.

[phallicies]

" I'd still like to see the segment score in the tab window, though." <- great idea