This milestone represents the point at which we will merge our current dev branch into master, representing a refactor of our core key management that supports multiple key signing strategies.

This may not actually include any of the features of managing multiple account types, but instead right now represents the more immediate goal of treating the refactored branch as our new main branch, and publishing it.

This includes auto-migrating previous metamask users' vaults, as well as warning users who experience account changes due to fixing BIP44 derivation, and otherwise represents feature parity and stability of the dev branch.