Declare DNS support as feature

sshuttle/methods/__init__.py

@@ -39,6 +39,7 @@ class BaseMethod(object):
         result = Features()
         result.ipv6 = False
         result.udp = False
+        result.dns = True
         return result
 
     def get_tcp_dstip(self, sock):

sshuttle/methods/tproxy.py

@@ -107,8 +107,10 @@ class Method(BaseMethod):
         result.ipv6 = True
         if recvmsg is None:
             result.udp = False
+            result.dns = False
         else:
             result.udp = True
+            result.dns = True
         return result
 
     def get_tcp_dstip(self, sock):