port list confusion

[Ryan Schmidt]

The `port list` command is confusing to many users: https://trac.macports.org/wiki/FAQ#portlist

I don't think I've ever used it myself to actually find out anything. If I'm searching for a port, I use `port search`. And if I already know what port I want, then I'm either trying to get information about it (`port info` or `port deps` or `port variants`) or see if and how it's installed (`port installed`) or if it's outdated (`port outdated`). If I just want to see what ports match an expression, I usually use `port echo` since `port list` is slow: https://trac.macports.org/ticket/34561

Users who use `port list` are probably coming to MacPorts from another platform where `list` is the correct subcommand. Taking just one example, `npm list` is the correct way to see what npm packages are installed.

I'd love to combine all the "list view" commands MacPorts offers into a single new `port list` command that shows all the information one would want. Then `port outdated` would become an alias for `port list outdated` and `port installed` would become an alias for `port list installed`. I think this would reduce confusion.

I'd like to solicit ideas for what the output of this hypothetical new `port list` command would look like.