Monitor elasticsearch and redis statistics

It adds the following raw metrics and a few useful charts to the stats-viewer. Most notably, this will help monitor import and indexing rates.

 * `collectd/elasticsearch-elasticsearch/bytes-indices.store.size/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.indexing.index-total/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.get.missing-total/value`
 * `collectd/elasticsearch-elasticsearch/counter-jvm.gc.time/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.search.fetch-time/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.search.query-time/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.search.query-total/value`
 * `collectd/elasticsearch-elasticsearch/gauge-http.total_open/value`
 * `collectd/elasticsearch-elasticsearch/counter-transport.rx.count/value`
 * `collectd/elasticsearch-elasticsearch/gauge-http.current_open/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.indexing.delete-total/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.get.exists-time/value`
 * `collectd/elasticsearch-elasticsearch/gauge-transport.server_open/value`
 * `collectd/elasticsearch-elasticsearch/gauge-indices.search.query-current/value`
 * `collectd/elasticsearch-elasticsearch/gauge-jvm.threads.count/value`
 * `collectd/elasticsearch-elasticsearch/counter-transport.tx.count/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.indexing.index-time/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.get.missing-time/value`
 * `collectd/elasticsearch-elasticsearch/bytes-jvm.mem.non-heap-used/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.get.time/value`
 * `collectd/elasticsearch-elasticsearch/gauge-indices.docs.count/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.search.fetch-total/value`
 * `collectd/elasticsearch-elasticsearch/gauge-process.open_file_descriptors/value`
 * `collectd/elasticsearch-elasticsearch/gauge-jvm.threads.peak/value`
 * `collectd/elasticsearch-elasticsearch/bytes-jvm.mem.heap-used/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.indexing.delete-time/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.search.fetch-current/value`
 * `collectd/elasticsearch-elasticsearch/bytes-jvm.mem.non-heap-committed/value`
 * `collectd/elasticsearch-elasticsearch/bytes-jvm.mem.heap-committed/value`
 * `collectd/elasticsearch-elasticsearch/bytes-transport.tx.size/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.docs.deleted/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.get.total/value`
 * `collectd/elasticsearch-elasticsearch/bytes-transport.rx.size/value`
 * `collectd/elasticsearch-elasticsearch/counter-indices.get.exists-total/value`
 * `collectd/elasticsearch-elasticsearch/counter-jvm.gc.count/value`
 * `collectd/redis_info/gauge-uptime_in_seconds/value`
 * `collectd/redis_info/gauge-evicted_keys/value`
 * `collectd/redis_info/gauge-connected_clients/value`
 * `collectd/redis_info/gauge-db0-keys/value`
 * `collectd/redis_info/gauge-blocked_clients/value`
 * `collectd/redis_info/counter-commands_processed/value`
 * `collectd/redis_info/bytes-used_memory/value`
 * `collectd/redis_info/gauge-changes_since_last_save/value`
 * `collectd/redis_info/counter-connections_recieved/value`
 * `collectd/redis_info/gauge-connected_slaves/value`

It uses: [phobos182/collectd-elasticsearch](https://github.com/phobos182/collectd-elasticsearch) and [powdahound/redis-collectd-plugin](https://github.com/powdahound/redis-collectd-plugin).