Portable Profile import/export checked in.

[Robert kebernet Cooper]

This is still a bit rough, but it works. Here is a rundown of what
this does:

On the Manage screen there are now Import and Export buttons. When you
export it will:

1. Look at all your currently installed desklets.
2. Take the desklets that have <source> or <source-def> declarations
and package them with your preferences.
3. Package up all your non-security related ab5k runtime settings.
4. Spit out an .ab5k file.

The idea here is you can take that ab5k file and run it through the
importer. It will then take all the desklets from your other profile,
download them, install them, restore your preferences for each of
them, then re-init the DeskletManager environment.

Our curent desklets aren't installed for auto-updates yet, but we will
correct this soon. This does, however, put the onus on the desklet
developer to have a remote install URL in their desklet, because any
that are lacking an update URL will not be preserved in the portable
profile.

Eventually, we hope to have a profile service on AB5k.org where you
can register and sync your profile between machines so your desklet
state will follow you from machine to machine. For now, though, USB
keyfobs and email work. :D