Support multi dimensions.
Necessary for getting any metrics of StorageGateway.
Merge pull request #9 from fujiwara/multi-dimensions

Support multi dimensions.
If 'statistics[:datapoints]' is empty, it will output to a log
update travis setting
Merge pull request #11 from kenjiskywalker/add_empty_log

Add empty log
Add a link to Fluentd.org
Merge pull request #12 from kiyoto/master

Add a link to fluentd.org in README