Install and configure MySQL `clustercheck`

The clustercheck service can be used by HAProxy to monitor a members
current status / health, allowing us to intelligently route MySQL
queries to available / healthy members.

Change-Id: Ibacfe7093ca6f49f21842316385b6f02c2800804
Restart stunnel earlier in configure.d

stunnel should be started as part of configure.d.
Delaying the restart in the post-configure.d causes
MySQL connection errors for keystone db_sync.  This is
required for MySQL connection over SSL to work successfully.

Change-Id: I2eb4af2f2dd8b302979384dbe17b63b3397d33bf
Add pycrypto install to swift-proxy element

We've encountered an issue with memcache encryption of authtoken
entries on Swift proxies where the authtoken middleware errors
out since pycrypto isn't installed.  This has been exposed on
standalone Swift servers.  To fix the issue, we've modified the
swift-proxy element so that pycrypto is installed along with
keystonemiddleware and python-swiftclient.

Change-Id: I727087a85df7ed94fd0ecac86c78826328e644f4
Closes-Bug: #1393790
Fix element-deps file name

Rally and RDO-icehouse elements where using elements-deps file
for dependencies instead of element-deps (extra s)

Change-Id: I28b48a11e57306c0f31bb463cbdf10f6ea4ed127
Merge "Add pycrypto install to swift-proxy element"
Merge "Fix element-deps file name"
Merge "Restart stunnel earlier in configure.d"
Merge "Install and configure MySQL `clustercheck`"