Convert Snapbird to Node

### Todo

- [x] Check existing functionality
- [x] Remove 'custom' urls (hitting `proxy.php`) from front-end
- [x] Front end to access `/api/user` for access token
- [x] Restore twitterlib as submodule (currently on cdnjs)
- [x] Use access token with twitterlib to restore full functionality
- [x] Check out bug in searched count
- [ ] Automated tests?