* extract most of the target framework defintions out of the csproj
* remove every target framework mention from the sdk based csproj
* Move old style csprojes to use the projectversion too
* use better variable names
* use the nugetcoresrc and nugetclientssrc variables
This change resolves number of issues blocking VS15 build on a box with VS
"15" willow installed at non-default location:
- Discovery of msbuild 15.1
- Microsoft.Build.* dependency version
- VS15/VS14 facade package restore conflict
- Assembly references pointing to a default VisualStudio PublicAssemblies location
- Binding VisualStudioVersion to MSBuildToolsetVersion
Key changes:
- Added 'Debug VS14'/'Release VS14' **solution** configurations to control
projects built for specific "toolset", i.e target VS version
- Added `HintPath` to Microsoft.Build.* assemblies pointing to current
`MSBuildToolsPath`
- Added `VisualStudioInstallDir` property initialized with VS install path
from registry key
- Moved common project properties to `common.props`
- Project files cleanup
This change adds Newtonsoft.Json 9.0.1 under the netstandard dependency group. net45 will continue using 6.0.4 to match visual studio.
Removing unneeded imports.
Fixes https://github.com/NuGet/Home/issues/3233
Andy Zivkovic