fmbt.debug(): support post mortem debugging
fmbt.debug(): support post mortem debugging

fmbt.debug(post_mortem=True) launches debugger at exit
if there is an exception that can be debugged.

mixu-/fMBT,mixu-/fMBT,01org/fMBT,mixu-/fMBT,mixu-/fMBT,01org/fMBT,01org/fMBT,01org/fMBT,01org/fMBT,mixu-/fMBT