Added a plugin to check SSL certificate expiry times

This plugin connects to remote hosts and checks the HTTPS certificate
expiry time.

Example: https://munin.buddycloud.com/ssl-day.html
more sensible subdirectory name (ssl_certificates -> ssl)
Adding new plugins for 1.5 version
Fix response name
New riak plugin for get/put 95th percentile time

Commit includes: a new riak plugin to monitor the 95th percentile time between reception of client PUT/GET request and subsequent response to client. 
The structure of the plugin is based on the two previously existing ones.
Added ability to monitor check/resync status of raid arrays, bugfix with regexp check while empty @output[0]
added tinychat plugin
Google PageSpeed plugin added

imported from gnuheidix/munin-plugins
updated tinychat plugin to also monitor users broadcasting
Update tinychat_users_

changed the graph_category
Support SNI in the certificate checking

plugin was checking the first vhost rather than the correct vhost's ssl certificate validity.
Merge branch 'pr/358'
Merge branch 'pr/368'
Merge branch 'pr/370'
Merge branch 'pr/375'
Merge branch 'pr/376'
Merge branch 'pr/377'