Enable influxDB storage backend for Grafana

You use InfluxDB Grafana to store dashboards.
grafanaDB: true marks it for use as dashboard storage (applicable for
InfluxDB & Elasticsearch)
Merge pull request #1 from meson10/path_fix

This should fix Errors like:
Merge pull request #2 from meson10/influx_store

Enable influxDB storage backend for Grafana
Merge branch 'master' of github.com:echocat/puppet-grafana
Fixed missing commas that would break config.js