User generated save - closes #42

- adds a userGeneratedContent service
- adds http endpoint add http endpoint at POST /homes/:id/data
- adds unit tests
- adds curl http tests

lmk if you have questions :)
What does `rel` represent? Is that the question and `value` is the answer?

Does this mean that for three different answers I will make three API requests as the client?

Just making sure I understand this