Migrate to MongoDB driver

The Mongo DB backend was migrated to the official driver https://github.com/mongodb/mongo-go-driver.
Fixed Mongo DB auth issue.
Added auth tests for Mongo DB and Redis.

Log options

Options to log to stderr, stdout and a file are now available.

Go modules

This release adds Go modules support.

Mysql and file patterns fix

Mysql now supports a unix socket connection properly.

File patterns had a typo on the check that was introduced when adding mosquitto 1.5.x support. It's now been fixed.

0.1.0 mosquitto 1.5.X support

This release stabilizes support for mosquitto's latest versions. Check the readme for instructions on building for 1.5.X and 1.4.X.