Require promise and when
Add handlers
Make _loadData async
Use promises to handle load
Make put async
Assure options is an object
Add TODO marker
Make remove async
Make apply async
Make tests async
Add quickstart example
Indentation
Add isAvailable check
Add isAvailable check
Store options object
Maintain a hashmap of engines

This should be done better
Remove switch/case name-to-inst block
Make engine choice async
Need to increment before
Cleanup, comments