Changed playlist storage to use a link table instead of embedded list.

service/src/main/sql/migrations/20151209054632-initial-schema-up.sql

@@ -15,10 +15,18 @@ CREATE TABLE tags (
 CREATE TABLE playlists (
   id SERIAL PRIMARY KEY,
   name VARCHAR NOT NULL,
-  media_file_ids INTEGER[] NOT NULL,
   mod_count INTEGER NOT NULL DEFAULT 0
 );
 
+CREATE TABLE playlists_media_files (
+  playlist_id INTEGER NOT NULL,
+  media_file_id INTEGER NOT NULL,
+  position INTEGER NOT NULL DEFAULT 0,
+  FOREIGN KEY (playlist_id) REFERENCES playlists(id),
+  FOREIGN KEY (media_file_id) REFERENCES media_files(id),
+  PRIMARY KEY (playlist_id, media_file_id)
+);
+
 CREATE TABLE bookmarks (
   id SERIAL PRIMARY KEY,
   name VARCHAR,