Clarify some of the password reset docs

      :file:`registration/password_reset_form.html` if not supplied.

    * ``email_template_name``: The full name of a template to use for

      generating the email with the new password. Defaults to

      generating the email with the reset password link. Defaults to

      :file:`registration/password_reset_email.html` if not supplied.

    * ``subject_template_name``: The full name of a template to use for

      the subject of the email with the new password. Defaults

      the subject of the email with the reset password link. Defaults

      to :file:`registration/password_reset_subject.txt` if not supplied.

      .. versionadded:: 1.4

    * ``password_reset_form``: Form that will be used to set the password.

      Defaults to :class:`~django.contrib.auth.forms.PasswordResetForm`.

    * ``password_reset_form``: Form that will be used to get the email of

      the user to reset the password for. Defaults to

      :class:`~django.contrib.auth.forms.PasswordResetForm`.

    * ``token_generator``: Instance of the class to check the password. This

      will default to ``default_token_generator``, it's an instance of

    * ``token_generator``: Instance of the class to check the one time link.

      This will default to ``default_token_generator``, it's an instance of

      ``django.contrib.auth.tokens.PasswordResetTokenGenerator``.

    * ``post_reset_redirect``: The URL to redirect to after a successful

      password change.

      password reset request.

    * ``from_email``: A valid email address. By default Django uses

      the :setting:`DEFAULT_FROM_EMAIL`.

    * ``uid``: The user's id encoded in base 36.

    * ``token``: Token to check that the password is valid.

    * ``token``: Token to check that the reset link is valid.

    Sample ``registration/password_reset_email.html`` (email body template):