talk to servers on non-standard https port (like -s acme.example.org:8443)

note:

I removed Network.server attribute, it was not used (only .server_url is used).

I also removed the sanity-check for the ACME server (so one can use server:port syntax, which was considered invalid).
I don't think this sanity-check is needed, because in the end, we can't fully check if it is correct anyway (you can always
give valid, but non-working server names or ports).
Also, many people will use the default ACME server, which is builtin and correct.

letsencrypt/client/client.py

@@ -59,7 +59,6 @@ class Client(object):
         :type dv_auth: :class:`letsencrypt.client.interfaces.IAuthenticator`
 
         """
-        sanity_check_names([server])
         self.network = network.Network(server)
         self.authkey = authkey
 

letsencrypt/client/network.py

@@ -17,13 +17,12 @@ logging.getLogger("requests").setLevel(logging.WARNING)
 class Network(object):
     """Class for communicating with ACME servers.
 
-    :ivar str server: Certificate authority server
+    :ivar str server: Certificate authority server (server[:port])
     :ivar str server_url: Full URL of the CSR server
 
     """
     def __init__(self, server):
-        self.server = server
-        self.server_url = "https://%s/acme/" % self.server
+        self.server_url = "https://%s/acme/" % server
 
     def send(self, msg):
         """Send ACME message to server.