CLC-1761 - Implement new dashboard designs

https://jira.media.berkeley.edu/jira/browse/CLC-1761

* Fix header background on small screens
* Update disabled button state
* Consolidate white colors
* Show canvas icon in tasks
* Fix adding / completing / deleting and clearing completed tasks
* Fix logging deleting tasks
* Hide campus classes in JS instead of HTML so we don't see a border on the last item in the widget
* CLC-1854 - CalCentral Logo is smaller in FF
* Hide the list bullets in FF