Added human readable dates for post times
* Added human readble date filter
* Filter has three output formats:
  * If date is today (e.g. Today at 12:34:20 PM)
  * If date is this year (e.g. April 3, 9:24:12 AM)
  * If date past a year (e.g. April 3, 2013, 9:24:12 AM)