Strong name the package

As a consumer of the NuGet package I like the project to be strong named, to be able to strong name my own project.

1. Generate a key.
    `sn -k UUID.Net.snk`
3. Add the following to project files:
    ```
    <SignAssembly>True</SignAssembly>
    <AssemblyOriginatorKeyFile>UUID.Net.snk</AssemblyOriginatorKeyFile>
    ```