Handling of Tiger-specific bug reports

[Joshua Root]

As has been touched on before, Tiger is well and truly unsupported as
per our "current and immediately previous OS release" policy. However,
there are still quite a few open tickets in Trac that are reported
against MacPorts running on Tiger.

I would suggest we start doing the following for tickets that are known
to only affect Tiger:

1. If it's a really easy one that doesn't require having a Tiger machine
to test on, just fix it.

2. If a patch has been supplied that looks reasonable, apply it in a
'platform darwin 8' block.

3. If neither of the above apply, and the port has no maintainer,
immediately close the ticket as 'wontfix'.

4. If none of the above apply, assign to the maintainer, with the
expectation that they should feel free to immediately close the ticket
as 'wontfix', but may choose to work on a fix if desired.

(1. and 2. would of course be done by the maintainer in the case that
there is one. But hopefully you get the idea.)

Tickets that only affect Tiger should be tagged with 'tiger' in their
keywords. Note that a ticket being reported by a user who is running
Tiger does not automatically mean the problem is Tiger-specific; you
should check if it can be reproduced on a supported platform.

- Josh