Add a plugin for enhancing imagery within bands of content

* Add a wdn-flipbook class for creating flipbooks of figures
* Add wdn-locked & wdn-scroll classes for side-by-side content display
Add examples for enhanced band imagery
Add newlines to eof
Whitespace consistency
Add a few omitted closing and opening tags for HTML cleanliness
Whitespace, alignment for readability
Add local variable for
Combine sequential CSS calls
Use DOM & avoid multiple calls to CSS selector engine
Use a sensible variable name for
Combine sequential variable assignments
Add local vars for parent & window height to prevent multiple calls
Remove unnecessary toString() calls
Move imagery update into a reusable function
Debounce updateImagery method for improved performance
Remove extra variable
added wdn-icons for social media
Merge pull request #589 from rklus16/wdn-icons

added wdn-icons for social media
Merge branch 'develop' of github.com:unl/wdntemplates into develop
Upgrade UNL_Templates PEAR library