Fixed #18819 -- fixed some typos in the auth docs

Increasing the work factor

~~~~~~~~~~~~~~~~~~~~~~~~~~

The PDKDF2 and bcrypt algorithms use a number of iterations or rounds of

The PBKDF2 and bcrypt algorithms use a number of iterations or rounds of

hashing. This deliberately slows down attackers, making attacks against hashed

passwords harder. However, as computing power increases, the number of

iterations needs to be increased. We've chosen a reasonable default (and will

down, depending on your security needs and available processing power. To do so,

you'll subclass the appropriate algorithm and override the ``iterations``

parameters. For example, to increase the number of iterations used by the

default PDKDF2 algorithm:

default PBKDF2 algorithm:

1. Create a subclass of ``django.contrib.auth.hashers.PBKDF2PasswordHasher``::