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.
We need to do this because when I tride to go to the JSON serializer a
bunch of tests started failing because various parts of our code are
putting things into the session that are not JSON serializable.
We can't keep using the default pickle serializer because it defaluts to
using the highest available protocol and that will cause issues with the
python 2 to 3 upgrade since both will be running in production at the
same time. We need to use a version of the pickle protocol that both
can use interchangably.
We also need to make sure we read with latin1 encoding to make datetimes
work correctly between the two versions of python.
