[Bug-gnubg] Help entering commands

[Jon Kinsey]

I've checked in a small change to add help as you type commands (with
edit->enter command).
I may well add a drop down box with the last few entered commands in too.
Any comments welcome...

I found a couple of small bugs when I was doing this:
1) Start gnubg and try an annotate command, crashes gnubg - I guess an extra
check is needed in these commands.
2) The help for the first command mentions games and moves but only "first
game" seems to work.

Jon