In the normal case the user probably wants to set break point or
anything when running an app in gdb, we should let him a chance to
do so.
In the case he is running in a loop, it probably means he want to
reproduce a crash or a race inside gdb so we should just go and
run in gdb.
We probably miss a few options to give him more control.
Knowing whether a test failed to run as its prerequisites were not
available, or whether those prerequisites were available and produced
unexpected/incorrect results, is a useful differentiation.
Add support for skipped tests by testing for exit code 77, used through
autotools/piglit/etc to denote a test which detected this and decided to
skip.