[Bug-gnubg] Integration of the move record and analysis panels

[anthon]

Hi, all

I suggest that we integrate the move record and analysis panels in to
one, with one tab for the move record, one for checkerplay and one for
the cube analysis.

The current situation is sub-optimal since too few moves are shown in
the checker tab of the analysis window and the move record is also a bit
short with the both panels open.

Christian.