Add class to allow left-aligned text

Useful for row-level `th`
Merge branch 'release-3.1.15' into develop
Update analytics_scroll_depth.js
Merge pull request #447 from cmdprompt/patch-1

Update analytics_scroll_depth.js
Merge pull request #437 from smeranda/its-justified

Add a class to allow override of `th` text alignment.
Revert "Use correct CSS3 linear-gradient syntax."

This reverts commit 1e1b1556d8ec7ac989f4e65650741ffd48d2c3c2.
Use the correct W3C syntax for linear-gradients.
See #392.
Fix CSS validation for various properties
Remove opacity hacks that were supposed to fix Windows font rendering
These hacks had little success and the webkit-font-stroke made rendering
on Windows Chrome look horrible.
Merge branch 'develop' of github.com:unl/wdntemplates into develop
Bumped dependency version number to 3.1.16
Merge branch 'release-3.1.16'