Restore 'none' in Campaign reports - there's no reporting since the Jan 17 release

[#1]

The so-called improvement added in the Jan 17 release in the way 'none' is handled is a bad idea in Campaign reports.

"A change was made to the way "None" is attributed when linear attribution is selected. "None" now receives credit only when it is the only value receiving credit. If other values are receiving credit, credit is allocated to those values and "None" receives no credit."

This means there are no metrics of carts/checkouts/orders/revenue etc. for the None channel - ie. all the Direct traffic is gone!