Versioned resources and progress towards an API

We have improved the consistency and simplified how Guardian is configured.

Most resources can be set through the guardian-cli apply command and can be retrieved through the guardian-cli get command.

In addition to simplifying the configuration from the CLI's perspective, this work was done in order to version the resources stored within Redis, to provide some consistent metadata to the various resource kinds, and to ensure that Guardian only interprets resources with the appropriate version. This is some of the ground work we wanted to complete before rolling out a more robust API server that should prevent the caller of guardian-cli needing direct access to Redis.

Some work has to be done in order to upgrade from v0.1.0 (or any prior Commit in the master branch) to v0.2.0. Please see the Wiki page for more information. This can be done in place, so following the guidelines will allow you to upgrade to the new version without any downtime or misconfiguration.