Merge pull request #142 from OctoPrint/v3-image-migration

V3 image migration

Merge pull request #135 from OctoPrint/enable-backup-restore

Enable backup restore

Merge pull request #88 from OctoPrint/feature-optional-mjpeg-streamer…

…-startup

Feature optional mjpeg streamer startup

Merge pull request #74 from OctoPrint/add-octoprint-back-to-base-image

Add octoprint back to base image