Feature request from seansan, posted on GitHub Jul 25, 2015
Request for ability to add new cart rule action - type cart id
Now it is not possible to give a discount on the FIRST item only
For instance we have a deal: the first T-shirt with 50% off ... (as a try out)
If the cart ID can be used in a rule action then this is possible
Concrete: please add cart id as a new rule type