ipapython.secrets.kem: Use ConfigParser from six.moves

In Python 3, the module name changed from 'ConfigParser' to
'configparser'. Use the appropriate location from six.

Part of the work for: https://fedorahosted.org/freeipa/ticket/4985

Reviewed-By: Martin Basti <mbasti@redhat.com>

ipapython/secrets/kem.py

@@ -2,7 +2,7 @@
 
 from __future__ import print_function
 from ipaplatform.paths import paths
-import ConfigParser
+from six.moves.configparser import ConfigParser
 from cryptography.hazmat.backends import default_backend
 from cryptography.hazmat.primitives import serialization
 from cryptography.hazmat.primitives.asymmetric import rsa, ec
@@ -154,7 +154,7 @@ class IPAKEMKeys(KEMKeysStore):
 
     def __init__(self, config=None, ipaconf=paths.IPA_DEFAULT_CONF):
         super(IPAKEMKeys, self).__init__(config)
-        conf = ConfigParser.ConfigParser()
+        conf = ConfigParser()
         conf.read(ipaconf)
         self.host = conf.get('global', 'host')
         self.realm = conf.get('global', 'realm')