Orphan list

First two tasks of PT story https://www.pivotaltracker.com/story/show/76239760

- [x] Create Orphan List model
- [x] Create new and index views for orphan lists
- [ ] Write cucumber features for testing orphan list creation and file upload 
- [ ] Switch to S3 for file storage
osra_num is just a friendly id the users will use to refer to uploaded lists instead of exposing them to the db ids.