Failure in cashaddr Send screen address field

[winchell]

Pasting a cashaddr to the Send screen address field fails unless bitcoincash: prefix exists in the pasted string. This conflicts with the cashaddr spec:

When presented to users, the prefix may be omitted as it is part of the checksum computation.

https://github.com/Bitcoin-UAHF/spec/blob/master/cashaddr.md

So people are going to be copying the address without the prefix, and the Send screen should work the same either way.