Adds support for post_class

See: http://codex.wordpress.org/Function_Reference/post_class
Merge pull request #122 from slimndap/patch-1

Adds support for post_class
updated change log
Merge branch 'dev'

* dev:
  updated change log
added `| array` filter
cleaned-up filters in twig file
updating change log and version number
Merge pull request #124 from WL-hohoho/master

Added time_ago filter translation possibility
Merge branch 'master' of github.com:jarednova/timber

* 'master' of github.com:jarednova/timber:
  added time_ago filter translation
adding note about time_ago to read me
fixed typo in readme