This makes it possible to check from another extension whether the
user has strong login security, without depending on internals
which can change at any time.
(The TwoFactorEnabled hook was intended for something like this
but it operates on $wgUser which makes it useless for logins.)
Change-Id: Ie15c45c9b29de0a0f926c2467808ca144f05e866
During the two-step login, users with OATH enabled need to have their
login details saved into their session while we prompt them for their
OATH code. This encrypts that data, so we don't write their user's
password into our session storage.
Change-Id: I9969871205ac5c438706df41ef1519cb4cd7a964
