Fixing broken hostnames in pingerd

Gauge type override logic for blob series

Some vendors like Fortigate publish sensor values as OCTECTSTR
instead of doing like Cisco and scaling the value. This commit
will export metrics that can be fully (all values) converted to
float as a gauge series.

Abort annotation if resolution fails

Current behavior is to use the value as the annotation, which is wrong.
Apparently this is odd enough for us not to have noticed before.

Remove 'type' field from SNMP metrics

This closes #21

Hack to make Travis deploy work

Merge pull request #10 from dhtech/annotator

A lot of annotator features

Use tags if available, otherwise use branch