Edited Issue: nuget.exe update not extracting package [2693]

From comments in #2661:

Current nuget.exe (2.1.0) now creates the package directories inside ".\packages" on "update" but only copies the .nuget file (and the .nuspec file) there without extracting its contents ("lib" folder) so even the "install" command I'm usually calling afterwards does nothing as it thinks it's already there -- but every assembly references are broken now since they point to assemblies inside "lib" folder which does not exist.