* wrap/python/cgi-bin/ltl2tgba.in (dot): Use the value computed by
configure.
(os.system): Cleanup stale files only when the form has been
submitted.
(list options): Keep track of the selected value.
(draw_acc_run|print_acc_run): set ec=0 to detect if it has been
later set or not.  Fix error message when using generalized
automata with degeneralized emptiness checks.
* wrap/python/cgi-bin/Makefile.am (ltl2tgba.py): Substitute @DOT@.