dragonfly handbook suggestion

[Justin C. Sherrill]

> I'm a dragonfly noob and I am in the process of building a custom
> dragonfly
> kernel. Just installed dfly from the iso, cvsuped a src tree and I was
> following this page of the manual when I got stopped on the first step.
> Apparently I needed to do a "make buildworld" before I could do step 1:
>   # make buildkernel KERNCONF=MYKERNEL
>
> Perhaps you could mention something on this page that suggests you may
> have to
> do a make buildworld before you can do step one. So other noobs don't get
> confused. :)

If you hadn't updated your source tree with cvsup, it wouldn't have
complained... but then again, it didn't mention that, either?  I don't
know how soon I'll have a chance to work on that, but yes, you're right. 
The handbook in general is somewhat unsuccinct, in part due to it being
mostly inherited from the FreeBSD Handbook.