v0.1-b.8 - Fix errors

[pyneda]

The following errors have been detected and fixed:

Traceback (most recent call last):
  File "sharesniffer.py", line 514, in <module>
    shares = sniff_network()
  File "sharesniffer.py", line 335, in sniff_network
    shares['nfsshares'] = sniff.get_nfs_shares(hostlist_nfs)
  File "sharesniffer.py", line 112, in get_nfs_shares
    for share in openshares:
UnboundLocalError: local variable 'openshares' referenced before assignment

Traceback (most recent call last):
  File "sharesniffer.py", line 514, in <module>
    shares = sniff_network()
  File "sharesniffer.py", line 336, in sniff_network
    if len(shares['nfsshares']) > 0 and not args.quiet:
TypeError: object of type 'NoneType' has no len()

[shirosaidev]

thanks for the patch