Support non-JS backend recipes

[JordanMartinez]

We have a few stable / pretty mature non-JS backends. I'd like to make it possible for someone to write make HelloWorld-<backend> and see the results of that. This would likely help raise awareness of PS' other backends and help those backends get more manpower support.

For example:

# what we currently have
make HelloWorld-node
make HelloWorld-web

# what we could have (simple)
make HelloWorld-python
make HelloWorld-go
make HelloWorld-c

# what we could finally have (complex)
make FpFullStack-web-halogen # uses Halogen for front-end
make FpFullStack-web-react # uses React for front-end
make FpFullStack-node # uses Node.js for server
make FpFullStack-python # uses Python and Django for server?
make FpFullStack-go # uses Go for server
make FpFullStack-c # uses C for server

Note: this issue does not need to be solved before we notify the larger community that it's ready for recipe requests.