Merge pull request #14 from sempr/master

MOD: fix mongodb_replset_lag bug, oldest_secondary_optime is a int value
Add current bytes stored plugin for memcached
Add limit_maxbytes to memcached_curr_bytes
Add indextank_index_size plugin
Fix an IndentationError by replacing a tab with spaces
Merge pull request #15 from prismskylabs/master

Fix an IndentationError by replacing a tab with spaces
mysql: add support for mysqlopts and mysqlconnection env variables

Also, add a mysql_connections plugin
Merge pull request #1 from samuel/master

merge new commits