* Implement `links` via optional interfaces
* Updating example app to include links
* Update readme with links information
* Exclude a slice relationship only if the slice is empty AND there are no defined links
* Remove `Link` in favor of vanilla `map[string]interface{}`. More flexible for different allowed links spec implementations.
* Update app.go with correct Links methods
* Use LinksObject and LinkObject types along with type assertion to provide errors when marshaling an invalid links JSON API object.
* Renamed LinksObject Links and LinkObject Link
* Added back the relationship link post merge.
* Renamed the JSON* Linkable functions JSONAPI* such that when a library user implements the interface it is clear the functions are used for JSON API as opposed to JSON
* Example cleanup.
* Refactor the example to use constants from jsonapi and http.
Kyle Truscott
Aren Patel
Luke Young
Harry Moreno
Sam Woodard