Implement an offset anchor dynamic CSS class.

`.wdn-offset-anchor` is generated at runtime to use the calculated
navigation bar size.

Closes #667
Initial styling updates to notices
Border, padding, subtle drop shadow updates
Use our own instance of html_codesniffer

Our version will usually have newer updates and is the same as the one included in webaudit.unl.edu
Fix contast issues with carousel

The carousel controls were failing contrast after the update due to an rgba background.  It was comparing the solid text to the background, which was failing.  This is actually an invisible change, because the text is not actually visible.
Fix contrast issues with events

These are rgba related fixes
Fix contrast issues with tables

These are rgba related fixes
Merge pull request #770 from mfairchild365/tests-accessibility

Use html_codesniffer hosted by UNL for accessibility testing
Update styling of notices
Reduced opacity on subheads for accessibility compliance, created examples typography file for inclusion in testing
Merge pull request #773 from skoolbus39/wdn-subhead

Increase contrast for .wdn-subhead
Merge pull request #772 from skoolbus39/wdn-notice

Update styling of notices
Decouple the notices less file and text less file

They are separate modules that export too much if imported. Only mixins
should be imported.
Correct the input group styles for responsive sizes

This makes the input groups work again with the form styles from Ryan
Merge pull request #774 from skoolbus39/wdn-quote

Update styling of quote
Bumped dependency version number to 4.0.15
Update webfonts to include extended Latin characters
Update favicon
Improved pixel-fitting of favicon
Merge pull request #776 from skoolbus39/wdn-assets

Update favicon