add gitignore
Don't generate M_Const/M_Enum.mch
abstract error machines
don't check in Machines_B directories
specify xml ast
factor test runner cases
test -ps option
test -pn option
test -pe option
specify ps/pn/pe for all *.test cases
dedup print_e_list
print slice
print index list
print_id_list
print_lambda_list
print_cond_list
print_e_list
print_slice_list
print_index_list
print_id_list