Throw proper exception on re fail

[helpdeskdan]

re.match - throw exception instead of crash!

./do_auth.py -i 1.1.1.1 -fix_crs_bug -u rancid -d 2.2.2.2 -l log.txt -f do_auth.ini -D
Traceback (most recent call last):
 File "./do_auth.py", line 571, in <module>
   main()
 File "./do_auth.py", line 430, in main
   if not match_it(this_group, "host_allow", ip_addr, config, log_file, filename):
 File "./do_auth.py", line 292, in match_it
   if re.match(item,match_item):
 File "/usr/lib/python2.7/re.py", line 137, in match
   return _compile(pattern, flags).match(string)
 File "/usr/lib/python2.7/re.py", line 242, in _compile
   raise error, v # invalid expression
sre_constants.error: nothing to repeat

[jathanism]

I know it's quite a bit late. Did we already fix this one?

If not, let me know what's inside of the do_auth.ini that could be used to repeat this.

Also, which Python version? Thanks!