Use entrain flag in EntrainAudio to decide to morph or not

The EntrainAudio message now has a flag that tells us whether or not we
should actually entrain the provided audio file, or whether we should
just generate energy for it, and stream it, the energy, and visemes
without entrainment.

src/entrain_speech_node.py

@@ -491,8 +491,9 @@ def on_entrain_audio_msg(data):
         # Create outfile name.
         out_file = os.path.basename(data.audio.replace(".wav", "")) + t + ".wav"
 
-        # If we have audio data to use as a target, save it and entrain to it.
-        if len(audio_data) > 0:
+        # If we have audio data to use as a target, and we are supposed to
+        # entrain to it, then we should save it and entrain to it.
+        if len(audio_data) > 0 and data.entrain:
             # Save audio collected so far to wav file.
             entrainer.save_to_wav(audio_data, target)
             # Reset audio data.
@@ -503,8 +504,11 @@ def on_entrain_audio_msg(data):
             # file (that we collected) to Praat for processing.
             success = entrainer.entrain_from_file_praat(target, data.audio,
                     out_file, full_audio_out_dir, data.age)
+        elif not data.entrain:
+            print "We were told not to entrain. Skipping entrainment."
         else:
-            print "No audio data to entrain to... skipping entrainment."
+            print "We were supposed to entrain, but we had no audio data to " +\
+                    "entrain to... skipping entrainment."
 
         # Adjust the viseme file times to match the morphed audio.
         visemes = entrainer.process_visemes(data.audio, out_file,