Tornado requires two sockets to support IPv6

Tornado sets setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
to force IPv6 sockets to only be used for IPv6 connections.  create a
separate socket to allow for CouchPotato to be used over IPv6.

couchpotato/runner.py

@@ -244,11 +244,13 @@ def runCouchPotato(options, base_path, args, data_dir = None, log_dir = None, En
 
     # Basic config
     host = Env.setting('host', default = '0.0.0.0')
+    host6 = Env.setting('host6', default = '::')
     # app.debug = development
     config = {
         'use_reloader': reloader,
         'port': tryInt(Env.setting('port', default = 5050)),
         'host': host if host and len(host) > 0 else '0.0.0.0',
+        'host6': host6 if host6 and len(host6) > 0 else '::',
         'ssl_cert': Env.setting('ssl_cert', default = None),
         'ssl_key': Env.setting('ssl_key', default = None),
     }
@@ -331,6 +333,7 @@ def runCouchPotato(options, base_path, args, data_dir = None, log_dir = None, En
     while try_restart:
         try:
             server.listen(config['port'], config['host'])
+            server.listen(config['port'], config['host6'])
             loop.start()
             server.close_all_connections()
             server.stop()