At least, the portion of it that we use.
Moved salting within the encryptor, so it does not need to be managed externally.
KeyringController now caches the password instead of a passwordDerivedKey, since it is ignorant of the salt.
Encryptor payload is now in a JSON format, so its portions are both base64 encoded *and* labeled appropriately. The format is `{ "data": "0x0", "iv": "0x0", "salt": "string" }`.
Fixes#843Fixes#859
Now old vaults are recognized as an "Initialized" MetaMask instance.
Upon logging in, when fetching the initial password-derived key, if there is no new-style vault, but there is an old style vault, it is migrated to the new format before proceeding through the usual unlocking steps.
