Consider removing the dp2mp upgrade code from base

[jmpp@…]

I looked around Trac but didn't find any ticket pertaining to my following proposal: we should start considering removing the dp2mp upgrade code from base (both base/Mk/macports.upgrade.mk and base/portmgr/dmg/preflight), as it's been quite a while since MacPorts 1.5.0, released on 09-July-2007, which is when my code saw the light of day.

The one big problem with this is that, if there happen to be any such incredibly-lagged-behind-stragglers, we'd be breaking any upgrade compatibility with them, for both their installed MacPorts release and their installed ports (i.e., they might as well rm -rf ${prefix}), given how extensively I changed the installation layout in the dp2mp move. So if we still want to make it smooth for them, we'd have to *explicitly* document a two-step upgrade process for them:

1. Installation from the last dmg containing the upgrade code, but *NOT* from anything newer than that;
2. Selfupdating to the latest release;

Ideas...?

-jmpp

[jmr@…]

Done in r53260. Now we just check for ${prefix}/etc/ports/dp_version and error out if it's present, with a message saying to install 1.7.1 first.