Add seriesid to episode. Fixes #72

src/imdb.ts

@@ -267,6 +267,9 @@ export class Episode extends Movie {
   /** what number episode in the season this episode is */
   public episode: number;
 
+  /** what series this episode is a part of (imdbid) */
+  public seriesid: string;
+
   /**
    * Creates an epsiode from results from omdb. This is not intended for consumer use.
    * Please prefer {@link TVShow.epsiodes}.

test/test-getReq.ts

@@ -118,7 +118,12 @@ describe("get", () => {
             "The Scorpion and the Toad",
             "testing returned title"
           );
-          assert.deepEqual(data.year, 2006, "testing correct year");
+          if (!(data instanceof imdb.Episode)) {
+            assert.fail("not an episode");
+          } else {
+            assert.equal(data.seriesid, "tt0460649", "testing seriesid");
+            assert.deepEqual(data.year, 2006, "testing correct year");
+          }
         })
     );
   });