Updated sln for new files

Author: Romanx

Stubble.Extensions.SystemData.sln

@@ -11,6 +11,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 	ProjectSection(SolutionItems) = preProject
 		.editorconfig = .editorconfig
 		.gitignore = .gitignore
+		appveyor.yml = appveyor.yml
 		licence.md = licence.md
 		readme.md = readme.md
 	EndProjectSection

Stubble.Extensions.SystemData/Stubble.Extensions.SystemData.csproj

@@ -48,6 +48,7 @@
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />
+    <None Include="System.Extensions.SystemData.nuspec" />
     <None Include="version.json" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />