Add json-ld recordingOf and recordedAs properties linking recordings and works.
Add composers, work parts, and arrangements to json-ld
Add lyricists to json-ld.
Add publishers to work json-ld output.
Merge branch 'json-ld-20141229' into beta

* json-ld-20141229:
  Add publishers to work json-ld output.
  Add lyricists to json-ld.
  Add composers, work parts, and arrangements to json-ld
  Add json-ld recordingOf and recordedAs properties linking recordings and works.