Make the Dashboard dropshadow a little lighter and turn panel management into a menu
- There's a very heavy dropshadow on panels right now that looks out of place. Reduce it a bit.
- Panels currently have unlabeled pencil and trash icons. Turn this into a menu. I'm likely planning to add options like "Change Query..." to this menu to make managing some types of panels easier.
Reviewed By: amckinley
Maniphest Tasks: T13272
Differential Revision: https://secure.phabricator.com/D20373