[Bug-gnubg] BUG: Stopping an evaluation inhibits more evaluations

[Ian Shaw]

Play a match and analyse it at 0-ply.
Pick a move, select a couple of plays and analyse them with the "3" button.
Press stop while the analysis is still running. (I hit the wrong button and 
it's taking forever.)
Try to analyse this move with the "2" button. Nothing happens.
Try to analyse another move with the "2" button. Nothing happens.

Go to a different game, and return to the original game. The buttons now work.

Version 0.14.2-dev 1.1539 040329 (build Mar 30 2004)

-- Ian