Including patches from bug-bash so far

- debug-trap.patch    from http://lists.gnu.org/archive/html/bug-bash/2014-02/msg00090.html
- test-nameref.patch  from http://lists.gnu.org/archive/html/bug-bash/2014-02/msg00093.html
- jobs-exit.patch     from http://lists.gnu.org/archive/html/bug-bash/2014-03/msg00017.html