cannot build some stable SDK components

[Jeff Johnson]

Certain parts of the stable SDK simply cannot be built in our current autobuild
configuration. These are the parts built out of the "packaging"
project--lsb-build-c++, lsb-build-qt3, and lsb-build-qt4.

This is because we build all of the pieces as a single build job. Part of that
job is only built from devel, and part of it has 4.1 and devel branches. Since
there is no 4.1 part for the major portion of the build, we must always build
that part from devel.

We should probably consider splitting up the current build-sdk build job into
build_env and "everything else", with the latter buildable in 4.1 and devel
variants. One potential problem: how to then assemble a complete SDK
automatically for use in the build slaves for subsequent jobs.