encypt passwords for test accounts

If these passwords are not encrypted, then you can only log in to the
test account once.  By default, the 'create_user' method does not
encrypt the password.  After the first login & logout, the password
is somehow changed in the database and the same password now fails.

See https://github.com/mattupstate/flask-security/issues/264

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>