This is to help diferentiate between passwords coming from
accounts, plugins, etc., and the master passphrase used in
an AES encryption key for encrypting these passwords.
Passwords are only decrypted before their actual use, not
while loading from accountrc.
Passwords are stored as "{algorithm}base64encodedciphertext",
encrypted using AES-CBC cipher, with PASSCRYPT_KEY used as
and encryption key.
Optionally, the encryption key, also known as "master password"
can be changed by user.
