Use uri_parsed['hostname'] for Tunnel config instead of uri_parsed['host']

http://nodejs.org/docs/latest/api/url.html host includes the port as well. So if my url in the proxy config is http://localhost:3128 then the tunnel config was 
"proxy" : {
          "host" : 'localhost:3128'
          "port" : '3128'
        }
Merge pull request #20 from caevyn/master

Use uri_parsed['hostname'] for Tunnel config instead of uri_parsed['host...