* Fixed stuff in the wall filter. Extended syntax:
--filter wall % open a wall (3x3 is the default value)
--filter wall:2 % open a 2x2 wall
--filter wall:3x2 % open a 3x2 wall
--filter wall:2x1:0 % open a 2x1 wall, only display block 0
--filter wall:2:0,3 % open a 2x2 wall, only display blocks 0 and 3
For instance, if you have 2 computers listening to a network stream, on
the left computer you use --filter wall:2x1:0 and on the right computer
you use --filter wall:2x1:1