ports/55515: [patch] extract perl stuff from bsd.port.mk into bsd.perl.mk

[Sergey Matveychuk]

The reason for the PR was to take perl related stuff out of bsd.port.mk. 
It would make possible to change it without interfering with not perl 
depended ports.

One and a half year has gone. I've tried to keep it up to date and to 
fix ports it makes broken (most bad formed perl depended ports).

There was plans for perl ports improvements after the PR committed but I 
  forgot most now.

Now it's out of date. I have neither physical nor mental power to care 
of it later. So it should be closed if nobody wants to care of it.

If you do and you have any questions, write me, I'll answer any of them.

-- 
Sem.