Many updates

Here are some changes I made to the assets plugin.  Can you review and let me know what you think?

There are still some changes that need to be made before this can be merged:

1) Change assets_route_regexp to only match known assets
2) Drop . to $2e encoding
3) Add much more comprehensive tests

Once this is fully ready, the branch should be squash rebased against master and not modify the version, but we aren't there yet.

The deadline for 1.1 is November 10, so if the plugin isn't ready by then, it will slip to 1.2.  That gives us a couple weeks to try to get this finalized.