Allow sharing of dotnet code

[jaknor]

Is your feature request related to a problem? Please describe.

sam-patterns-cli offers the ability to share code written in node, but does not offer the same capability to other languages. I would like to add the capability of sharing code in dotnet

Describe the solution you'd like

Make dotnet sharable in the runtimes.json file. Update the documentation with information about how to share code.

Describe alternatives you've considered

Additional context