Pypcap

- better lookupdev() on win32, as requested by Zack Payton
<zacktek-pros.com>

- add Linux SLL datalink type

- better threading support from A. Nonymous

- API CHANGE: require 'cnt' as first parameter to pcap.dispatch(),
shadowing libpcap pcap_dispatch().

- add pcap.{get,set}nonblock(), to work around broken BPF select()
on certain platforms (MacOS X, older FreeBSD, etc.).

$Id$