RFC: rework of bugbusting pages on the wiki

[Mark Linimon]

I've spent some time bringing the bugbusting pages up to date, and am
soliciting review.

 - The original text from the intro page is now in
   http://wiki.freebsd.org/BugBusting/StateOfBugbusting.

 - The new contents of http://wiki.freebsd.org/BugBusting are an index
   to all the other pages, together with some "start here" text.

 - http://wiki.freebsd.org/BugBusting/Resources has been completely
   reorganized by logical groups instead of by where the links appeared.

 - All of the new prototype GNATS reports are now referenced.

 - References to both John Baldwin's paper at BSDCan (about advanced
   kernel debugging) and my own (the state of bugbusting) have been
   added.

mcl