Added label_errors option for displaying errors in labels
Added label_errors to README
Merge pull request #144 from timcheadle/label-errors

Allow users to display validation errors in labels
Update CHANGELOG.md

Add #144 to features list
Use #underscore, not #downcase for help text scope
Support both #downcase and #underscore for help text's I18n scope
Refactor #generate_help_text