CONTENTBOX-237: Updated Actions buttons on dashboard and page/entry view...

...s to use pull-right class so that drop-downs don't overflow off the screen. Also added pull-left class to submenus on page/entry views so drop-down doesn't flow off screen

CONTENTBOX-231: Added keybindings for a number of events, including several in CKEditor. Added a method in contentbox.js to allow for specifying keybindings via html data; can handle either links or onclick events