Make dp download archives from a remote machine

[danielluke (Daniel J. Luke)]

This patch adds support for a new conf key, remotearchiveurl, if archive mode and this key is set to a webserver having darwinports packages, it will download the pre-build packages from the URL and use the package to install the port (instead of building it).

Patch is a little rough (due to my lack of serious tcl-foo), but it seems to work pretty well for me right now.

Intended behavior is to look for a local archive first, then the remote archive (if necessary), and then if necessary build the port normally.

Since it's fairly easy to point apache to a darwinports packages directory, this makes maintaining ports on multiple machines take less time (as each port only needs to be built once).

If we ever get around to auto-building ports, we could conceivably make packages available this way as well.

Patch will be attached shortly.

[danielluke (Daniel J. Luke)]

Enable archive mode to pull archives from a remote machine

[danielluke (Daniel J. Luke)]

updated patch