When selecting an account, we now persist the selection to the `configManager`, so the selection can be restored when re-unlocking Metamask.
Also found the bug where `rawtestrpc` was still being used as a default, and fixed it!
- When unlocking, the first account is now selected by default and displayed as the main view.
- There is now a "CHANGE ACCT" button on the detail view to show the accounts list.
- Clicking an account from the accounts list now navigates to the detail view and selects that account.
- Config/Info screen "back" buttons now fire a new action, `GO_HOME`, which is configured to navigate to the accountDetail view, putting that logic in one place.
- When locking and unlocking again, the first account is always displayed, eventually we should persist the selection.