Use the same readme for github and nuget

Author: jonteohr

GradientTheme/GradientTheme.csproj

@@ -62,7 +62,7 @@
         <XamlRuntime>Wpf</XamlRuntime>
         <SubType>Designer</SubType>
       </Page>
-        <None Include="docs/README.md" Pack="true" PackagePath="\" />
+        <None Include="../README.md" Pack="true" PackagePath="\" />
     </ItemGroup>
 
 </Project>