Organize emails by JIRA parent in Issues.

This required mirroring the JIRA and Crucible APIs within the server, because they do not send a cross-domain request header back, so I can't access them from JavaScript.

Also, expanded the definition of "email folder". Folders created outside of Outlook seem to have a nil type. I'm also specifically including folders I don't care about - Deleted Items, Drafts, and Junk E-mail.