Disable cache support when using validate

Since we never use any of the functionality when validating, we'll
disable it.

Change-Id: I8432acc4ff847a3e99bef10449969a01c8fc2795
Signed-off-by: Paul Belanger <pabelanger@redhat.com>

grafana_dashboards/cmd.py

@@ -85,6 +85,9 @@ class Client(object):
 
     def validate(self):
         LOG.info('Validating dashboards in %s', self.args.path)
+        # NOTE(pabelanger): Disable caching support by default, in an effort
+        # to improve performance.
+        self.config.set('cache', 'enabled', 'false')
         builder = Builder(self.config)
         try:
             builder.load_files(self.args.path)