Merge pull request #46 from neilang/master

Added placeholder data attribute
Fix assets
Version bump 2.3.0
Provide the response json to the error handler
Documentation on using the json response
Merge pull request #48 from 1uptalent/error_handling

Provide the response json to the error handler.
Removed trailing whitespace and normalized to use space chars, never tabs
Merge pull request #49 from 1uptalent/normalize_whitespace

Removed trailing whitespace and normalized to use space chars, never tabs
Version bump 2.4.0