[RP] a coupla bugs

[Rupert Levene]

Two little bugs:

1. gmerging a group with itself (i.e. ratpoison -c 'gselect 0' -c
   'gmerge 0') puts rp into a tight spin

2. Try

ratpoison -c "echo 123456789
."

   (with the newline). There's a half-highlight stuck between the
   lines. It's more apparent the more lines the string to be echoed
   contains.

All the best,
Rupert