NuGet.BuildTasks

This release added support for nuget.exe writing package repository locations into project.lock.json.

This release included initial support for referencing xproj projects from csproj projects, and fixed the following notable issues:

1. Adding some NuGet packages would cause the removal of references like "System". (NuGet/Home#1880)
2. Builds would give spurious errors about BeforeGenerateProjectPriFile. (NuGet/Home#1814)
3. PDBs should be copied along with DLLs if available. (NuGet/Home#2009)