Guidelines about trac tickets and pull requests

[Mojca Miklavec]

Hi,

I believe that we need some written guidelines about opening trac
tickets and pull request. Many people now open both at the same time.
That's not as bad when they are at least referenced properly (and
annoying when they are not), but it probably doesn't serve anyone to
have both.

(I believe that it might still make sense to open a pull request
referencing an existing bug report to simplify reviews or when
multiple commits are needed.)

But we should write those things down somewhere, perhaps at Ticket
guidelines (https://guide.macports.org/#project.tickets).

Mojca