front page tweaks
*think* I fixed issue w/ incorrect app state
eagerly load profile + messages regardless of first page
added back link to show message view
added icon to share link
moved some common styling into page-header mixin
added sender images to thread view
hide UI elements rather than display undefined
added title to show message view
adding an example of Mailgun data to the repo...

...to make development a bit easier
added sender_name and recipient_name to messages
added sender_name and recipient_name to JSON response
added sender_* and recipient_display_name helper methods
added user images to show message view