Package the net45 build of Newtonsoft.Json in the NuGet package

Fixes #1345

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers/StyleCop.Analyzers.nuspec

@@ -20,7 +20,7 @@
     <!-- Binaries and symbols -->
     <file src="bin\$Configuration$\StyleCop.Analyzers.dll" target="analyzers\dotnet\cs" />
     <file src="bin\$Configuration$\StyleCop.Analyzers.pdb" target="analyzers\dotnet\cs" />
-    <file src="bin\$Configuration$\Newtonsoft.Json.dll" target="analyzers\dotnet\cs" />
+    <file src="..\..\packages\Newtonsoft.Json.7.0.1\lib\net45\Newtonsoft.Json.dll" target="analyzers\dotnet\cs" />
 
     <!-- Scripts -->
     <file src="tools\install.ps1" target="tools\" />