bump version in config and datestamp release notes

Author: Dottenpixel

RELEASENOTES.general.md

@@ -1,7 +1,7 @@
 <!-- Release notes authoring guidelines: http://keepachangelog.com/ -->
 <!-- On release, add general notes here. In time the legacy release notes will be add to this -->
 
-## 2.16.0 - Upcoming
+## 2.16.0 - August 12, 2021
 
 - In accordance with ARIA 1.2 guidance, the `input` was replaced with `button` within these components that contain select-only comboboxes:
   - Datetime Picker

ui/_config.scss

@@ -9,7 +9,7 @@
 ///
 /// @type String
 /// @access private
-$app-version: "2.15.8";
+$app-version: "2.16.0";
 
 /// Debug mode (uncomment to activate)
 /// Turn on to output deprecation warnings during development