Add email

DONE with https://app.asana.com/0/11169835259596/11879618369261

Ok, this was a fairly involved assignment, and a real learning experience.  I had to rework my index view in order to be able to publish incoming emails as posts.  Prior to this branch, my publish capability was not working quite right, but now it does. I attached a screenshot in my sub-task in Asana which shows the log entries for an incoming email from my uw.edu gmail account, as well as the unpublished email/post in my app.  Outgoing email works fine and my rake test for this passes. 

No collaborators were used, but I did peek at what you had submitted to github for a hint now and then, particularly for the changes I needed to make to my Post index view.  I also watched the Railscasts several times to get a good feel for things, but there was some 'translation' required in order to apply it to this assignment.