Clean up some easy to fix warnings in the Java code.

src/com/googlecode/eyesfree/espeak/SpeechSynthesis.java

         nativeStop();
     }
 
-    @SuppressWarnings("unused")
     private void nativeSynthCallback(byte[] audioData) {
         if (mCallback == null)
             return;

src/com/googlecode/eyesfree/espeak/eSpeakActivity.java

 import android.widget.TextView;
 
 import java.util.ArrayList;
-import java.util.Locale;
 
 public class eSpeakActivity extends Activity {
     private static final String ACTION_TTS_SETTINGS = "com.android.settings.TTS_SETTINGS";