popups 6.x-2.0-alpha6

I just got on as a maintainer for this module so I'm trying to apply fixes we'd made for our sites back to the module. Hopefully it'll work as well for other people.

The two big improvements are compatibility with the jQuery Update module and the ability to use JS aggregation.

Changes since DRUPAL-6--2-0-ALPHA5:

• Don't show the drupal_set_message in a popup, unless it is the bottom of the stack.
• Cleaning up console.logs.
• #419974 by longwave, timtrinidad: IE6 compatibility patch.
• #442942 by zoo33: onUpdate option doesn't work.
• Removing all the trailing whitespace.
• #436094 by drewish: Enable CSS/JS aggregation.
• #468218 by DeFr and drewish: Compatibility with jQuery Update.