Replaced validation library to help with error handling

- Also fixed wrap-keyword-params
Added first attempt at error handling in the HTML layer

* Issue: in order to display HTML how I'd like, I need to let
  malformed? pass if the media-type is HTML, which seems hinky.

* TODO: Add error handling for other media types.

* Both enlive and liberator are macro-heavy and are frustrating me.
Better error handling -- gets the label as well as the input
Better JSON error handling
Merge pull request #6 from cndreisbach/error-handling

Error handling