show request can have jsonld context in path or params

- [ ] show request can have jsonld context in path or params
- [ ] updating rails to  4.2.0.rc1; 
- [ ] don't have routes or methods for unimplemented actions (editing annotations)
- [ ] test against more ruby versions on travis, including the one on the triannon-dev box and the one on my laptop.
- [ ] up version to 0.4.0