Add a bit more debug output.

This isn't needed to resolve the problems, but it's useful in other
cases.
Re-target .NET 4.0 in the Tests project.

The build machine doesn't have .NET 4.5 installed (yet), and the Web
project is targetting .NET 4.0 anyway. This should resolve some warnings
in the build log, but I don't think it will resolve the build failure.