Update puppet-ceilometer to latest master

Changes include:
 - Add support for configuring coordination/backend_url
 - Clean up stray copy-paste error
 - Release 5.0.0 - Juno

Hash references:
 - old commit: 1d78470
 - new commit: 64d872c

Author: Eoghan Glynn

Puppetfile

@@ -3,7 +3,7 @@ mod 'apache',
   :git => 'https://github.com/puppetlabs/puppetlabs-apache.git'
 
 mod 'ceilometer',
-  :commit => '1d78470e5023e2ca6adef47c904d14d046dd87d1',
+  :commit => '64d872cdef84867728087609996e5d9993398416',
   :git => 'https://github.com/stackforge/puppet-ceilometer.git'
 
 mod 'certmonger',