add timeout handling for gdb commands

add timeout handling for gdb commands

sometimes, commands simply don't return ...

the debug message doesn't say anything which couldn't be found in the
log already, but that way it is more convenient.

and we kill gdb to get creator back to a defined state.

Reviewed-by: hjk
(cherry picked from commit 0ae60ba412afba260d0211ec5eecfe110ae8cfa2)