Add MonitorActivity - for registering on network and sending audio

This commit adds the shell of the MonitorActivity. This activity
will register its service on the local network, wait for a connection,
then send audio data.

AndroidManifest.xml

@@ -24,6 +24,11 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <activity
+            android:name="protect.babymonitor.MonitorActivity"
+            android:label="@string/app_name"
+            android:parentActivityName="protect.babymonitor.StartActivity"
+            />
     </application>
 
 </manifest>