Add more security when confirming destructive actions

• Deleting an entity
• Deleting an entity that also appears within a collection.

AT:

• Refined text for clarity (see designs)
• Removed entity name in modal title
• Focus on the 'cancel' button and not the 'delete' button, lessen chance of destructive accidental input.

(OKR - Optimize becomes more business friendly)

Designs
-------
Destructive actions
http://zpl.io/aBWKO30

(screens are tagged with ticket number in Zepplin)