NuGet updates

## Big change (with release build instructions)

Explicitly reference the *transformed* XML documentation file which Sandcastle produces, instead of simply including the default one produced by the .NET compiler. This operation replaces tags like `<inheritdoc/>` which appear in the original source with the referenced documentation so IntelliSense features provide the complete and accurate documentation to users. This *also* means you must build the Sandcastle project before you can create the NuGet package, and the NuGet package will only include up-to-date xml documentation if the projects are built in the following order.

1. Build the `SimpleRestServices` project in the Release configuration.
2. Build the Sandcastle project (`src/Documentation/Documentation.shfbproj`) in the Release configuration.
3. Build the NuGet package with the following command.

        NuGet.exe pack SimpleRestServices.csproj -Prop Configuration=Release -Symbols

## Smaller changes

- Updated author field to use your actual name instead of username
- Updated copyright field to include "JSI Studios" (now matches the `[AssemblyCopyright]` attribute value)
- Added `xmlns` declaration to the nuspec file