Add $::galera_bootstrapped fact

This fact let puppet know if the node is part of a Galera cluster
already or not.

Change-Id: I4ff0512a0d15ac4797c8c64ed76c0fd3fc31b45c

lib/facter/galera_bootstrapped.rb

@@ -0,0 +1,19 @@
+# Copyright 2015 Red Hat, Inc.
+# All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+Facter.add('galera_bootstrapped') do
+  setcode do
+    FileTest.exists?('/var/lib/mysql/grastate.dat')
+  end
+end