ipaplatform: Add Debian platform module.

v2:
- use redhat_services.redhat_system_units.copy
- don't use wildcard imports
- add some empty lines to make pep8 happy

v3:
- make parse_ipa_version static

v4:
- make more methods static

v5:
- fix pylint issues
- use syntax that doesn't break with python3

v6:
- remove IPA_GETKEYTAB from paths, it's the same across distros

Reviewed-By: Stanislav Laznicka <slaznick@redhat.com>
Reviewed-By: Christian Heimes <cheimes@redhat.com>

ipaplatform/base/tasks.py

@@ -227,7 +227,8 @@ class BaseTaskNamespace(object):
         else:
             log.debug('user %s exists', name)
 
-    def parse_ipa_version(self, version):
+    @staticmethod
+    def parse_ipa_version(version):
         """
         :param version: textual version
         :return: object implementing proper __cmp__ method for version compare