Split and cleanup of Porters Handbook

[Mark Linimon]

I'm quite concerned that it will be more difficult to figure out when new
text was introduced, or old text was changed.  There have been several
times in the past that I have tried to find out "why is XYZ being done, is
that just something from the old days?  When was it introduced?" and have
been unable to, due to the fact that years ago there was some kind of
repocopy and split (off from the Handbook, perhaps?) and it's so obscure
that it's just not possible to track it all down.

I have had some ideas in the past on how to reorg the handbook in terms
of "policies (which will be enforced) vs. best practices (which is what
portmgr recommends", and further split the thing up into a Ports Users'
Guide vs. what really ought to be in the "Porter's Handbook", but I have
been far enough away from doc work for a while that I think I have to admit
I won't get around to this anytime in the next month or two.

mcl