Minor changes to sniffer
* modules/sniffer/sniffer.py
  -- Added the run() function to wrap the thread init and variable.
* modules/sniffer/database_sniffer.py
  modules/sniffer/http_sniffer.py
  modules/sniffer/password_sniffer.py
  modules/sniffer/traffic_sniffer.py
  -- Replaced inits with run()
* modules/dos/tcp_syn.py
  -- fixed run response