New features

Fixed below issues in this release
- https://www.drupal.org/project/cacheexclude/issues/2901486
- https://www.drupal.org/project/cacheexclude/issues/2922341

Issue #2929098 by kyberman, honzapara: Radial Gradient Modifier

Added settings page so that suppression of emails can be toggled on and off through the admin interface.
Set up override in settings.php, so that suppression of emails can be set in settings.php, preventing editing of the setting through the admin interface.

* Updated colour palette
* Updated logo
* Updated gulp file
* Packaging update to mirror Drupal core package versions
* Updated webpack configuration to only load lcoal rules
* Added license extraction from vendor js files into presto.js.LICENSE