Refactor settings

fixes https://github.com/bitpay/copay/issues/1113
fixes https://github.com/bitpay/copay/issues/1203
fixes https://github.com/bitpay/copay/issues/1290
fixes https://github.com/bitpay/copay/issues/1208

lol... this is so wrong in so many ways: `http//localhost:30001` read it carefully:
- default should be insight.bitpay.com
- it's not a valid URI: lacking `:` before `//`
- port 30001????
Wil fix