MAAS snap experience
In the pursuit of making it easier to consume MAAS and deliver a production ready MAAS in a few simple commands the MAAS project is switching from debs to snaps (snapcraft.io). Currently building all the debs for MAAS outputs 12 different deb packages and `apt install maas` installs a total of 164 new packages on a clean Xenial cloud image. I wanted to get this down to just one snap with all of the requirements bundled in that one snap. This was a challenge as the 12 different deb packages were created in such a way to allow different operating modes. DEB modes: `apt install maas` - Fully running MAAS with Postgres, regiond, and rackd. `apt install maas-region-api` - MAAS regiond with external database. `apt install maas-rack-controller` - MAAS rackd connected to remote region. `apt install maas-region-api maas-rack-controller - MAAS regiond with external database and rackd. To enable this I implemented a way of changing the operating mode of the new MAAS snap. This allows a