Fork protorpc into a protorpclite module.

ProtoRPC has a number of large features (remotes and services, WSGI/webapp
integration, etc) that we don't use, and are currently causing a bit of
friction for (internal) package management. Easy solution: fork.

This commit simply pulls in the relevant modules, and strips out some of the
bits we don't use. Going forward, it's quite possible that we can now clean up
much of apitools_base.encoding and apitools_base.extra_types by simply
modifying protorpclite.
27 files changed