This change updates things so that if a ConfigForm has fieldsets, they'll be

rendered correctly (as opposed to just having all the fields rendered together

as if the fieldsets didn't exist).
This has one small niggle in that if a person defines their own fieldsets, one

of those fieldsets must contain the form_target field. I've added a log

statement to help people figure out what went wrong if they didn't include

this.
Testing done:

- Ran unit tests.

- Used this in conjunction with a Review Board change.

Ran unit tests.
Used this in conjunction with a Review Board change.