Fix munin-node access control

In the development environment, the master server was being
denied access to connect.
Add Munin charts for memcached
Add script to get ES heap stats (refs #7738)
Add BigCouch/ES maintenance scripts (refs #7738)

* Add scripts to backup, restore, and compact BigCouch databases
* Add Elasticsearch heap stats script
Add gems needed for BigCouch restore script and chomp away newlines
WIP: shared install_ruby_tools script
Install rbenv and bundler successfully on central