Describe how to use the html_content option.

Used callout_editorial to drive out functionality but may need to
swap with a helper than actually uses that option.
Add Show n Hide component
Add CalloutEditorial helper
CalloutInstructional component
Add RangeInput component and example
Add FieldHelpText component and example
Add ButtonTertiary component and helper
Add ButtonSecondary component and example
Add ButtonPrimary component and example
ShowHide - insert content
Use html_safe to render markup
Slider - pass in fuller set of attributes
FieldHelpText - restore hardcoded id's on elements
Correctly name the field help text styling file
Add button types to style guide - directional and inline
form CSS - remove redundant classes
FieldFormatHint added to 'made with dough'
Add RangeInput component
Add ProgressIndicator component