Ensure presence of file to be serialized through one of the serializer modules
(see: https://docs.saltstack.com/en/latest/ref/serializers/all/index.html):

iteritems() was dropped in recent Python3 releases and items() is compatible
with Python 2.7.

Change-Id: Ia286ac4377c6b03ce16c9dc1a5c7d3441efe7e12

file.managed use "mode" option and not "file_mode" to configure the
perms of the managed file.
See: https://docs.saltstack.com/en/latest/ref/states/all/salt.states.file.html#salt.states.file.managed

Change-Id: Ibd0a024bcd69089d9835a18f2bb803c952e13967