Updating to the current highest number instead of making it the default which is highest know by the language. This is beacuse when we update between python versions if there is a new proctocol version, we don't want that to cause cache thrashing as we try to load things from the various caches. We can get into a situation where new machines pickle things with a newer versions of the procotocl, put them in the cache and then break older machines that don't know about the new protocol version.
common ------ This directory contains common code shared between LMS and CMS, such as Mako templates, CSS, and Coffescript.