Changes node to use ~~abc:~~ `ecash:` CashAddr prefix instead of bitcoincash: (with ~~abctest: and abcreg:~~ `ectest:` and `ecregtest:` for testnet and regressiontest, respectively)
~~edit: made 'bitcoincash:' backward compatible for now, and buplicated some of the tests that used it~~
~~Currently breaks a bunch of tests on the `abc:` setting.~~