Add winrepo_provider to master.d/f_defaults.conf

salt/files/master.d/f_defaults.conf

 
 #####  Windows Software Repo settings #####
 ###########################################
+# Specify the provider to be used for git_pillar. Must be either pygit2 or
+# gitpython. If unset, then both will be tried in that same order, and the
+# first one with a compatible version installed will be the provider that
+# is used.
+{{ get_config('winrepo_provider', 'pygit2') }}
+
 # Repo settings for 2015.8+ master used with 2015.8+ Windows minions
 #
 # Location of the repo on the master:
 alternative.mongo.{{ name }}: {{ value }}
 {%- endfor %}
 {% endif %}
-{%- endif %}
+{%- endif %}