The comment block at the end of the heap profile includes *almost*
everything from MemStats. Add the missing fields. These are useful for
debugging RSS that has gone to GC-internal data structures.

Change-Id: I0ee8a918d49629e28fd8fd2bf6861c4529461c24
Reviewed-on: https://go-review.googlesource.com/29276
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>