Add clarification in documentation of juce_AudioAppComponent.h

modules/juce_audio_utils/gui/juce_AudioAppComponent.h

@@ -30,10 +30,18 @@ namespace juce
 //==============================================================================
 /**
     A base class for writing audio apps that stream from the audio i/o devices.
+    Conveniently combines a Component with an AudioSource to provide a starting
+    point for your audio applications.
 
     A subclass can inherit from this and implement just a few methods such as
     getNextAudioBlock(). The base class provides a basic AudioDeviceManager object
     and runs audio through the default output device.
+
+    An application should only create one global instance of this object and multiple
+    classes should not inherit from this.
+
+    This class should not be inherited when creating a plug-in as the host will
+    handle audio streams from hardware devices.
 */
 class JUCE_API AudioAppComponent   : public Component,
                                      public AudioSource