Link to a user history page

* Add history to routes
* Add link to layout
Create HistoryController

* Create history object
* Add show method
Show user history page

* Show all of current user's posts
* Create a post partial to better display posts
Move variable declaration to controller to minimize role of view
Improve syntax of route for history#show
Move functionality of history to user show

* Remove history to make more RESTful and whatever
* Move functionality to user show
* Change routes, links accordingly
Merge pull request #10 from elijahkim/ha-my-posts

Let user view their post history