Refreshing balances should derive new xpubkey addresses and check to see if there were deposits

[coblee]

Abstract

When you refresh balances, you should check to see if there were coins sent to new addresses of xpubkeys

Motivation

People with xpubkeys will occasionally deposit coins to new derived addresses. It's important that refreshing balances catches those.

Specification

[LefterisJP]

This is easy. Let's just implement it in next release