Allow principal and keytab in cli config

Signed-off-by: Patrick Uiterwijk <puiterwijk@redhat.com>

cli/koji.conf

@@ -19,6 +19,12 @@
 ;the service name of the principal being used by the hub
 ;krbservice = host
 
+;the principal to auth as for automated clients
+;principal = client@EXAMPLE.COM
+
+;the keytab to auth as for automated clients
+;keytab = /etc/krb5.keytab
+
 ;configuration for SSL authentication
 
 ;client certificate

koji/__init__.py

@@ -1584,6 +1584,8 @@ def read_config(profile_name, user_config=None):
         'poll_interval': 6,
         'krbservice': 'host',
         'krb_rdns': True,
+        'principal': None,
+        'keytab': None,
         'cert': None,
         'ca': '',  # FIXME: remove in next major release
         'serverca': None,