TST: Update talib example for compatibility with multiple sids.

To support mulitple sids the TALib transforms now return a dict,
instead of a float. Accordingly, the TALib example script now needs
to index into the transform result.

zipline/examples/dual_ema_talib.py

@@ -63,8 +63,8 @@ class DualEMATaLib(TradingAlgorithm):
             self.sell = True
 
         self.record(AAPL=data['AAPL'].price,
-                    short_ema=self.short_ema,
-                    long_ema=self.long_ema,
+                    short_ema=self.short_ema['AAPL'],
+                    long_ema=self.long_ema['AAPL'],
                     buy=self.buy,
                     sell=self.sell)