Version 1.11 removed support for .NET 4.0 -- see #696. The intent was that NuGet would hide new, incompatible versions in projects targeting .NET 4.0. That proved not to be the case -- see #716.
#718 reintroduced support for .NET 4.0 into our generated (API-specific) libraries by creating two projects that target different PCL profiles. The Profile328 project will continue to support net40 but will depend on an old version (1.10) of Google.Apis, etc. The Profile239 project supports net45 and above and depends on the newest version of Google.Apis.
#713 brought our client generator into the repository as a subtree rather than as a submodule. That'll make it easier for us to coordinate changes in the generated and support libraries.
This release only includes generated libraries. The support libraries will remain at v1.11.1.