Fogbugz importer

Created by: szechyjs

This is nearly feature complete, but before I put the finishing touches on it I wanted to open a discussion and make sure I'm heading down the right path.

Since Fogbugz does not directly couple their repositories (Kiln) with their bug reporting this importer just creates a bare repository and then populates the issues, comments, and labels.

One thing that I would like to do as well is have it import attachments. I'm not sure the best route for going about this. During the import I have access to a URL of the attachment, this URL requires authentication/token with Fogbugz, so it would make sense to upload it as an attachment to gitlab.