Issue 2667802: [Audio Effect Framework] AudioEffect base class and JNI.

Added AudioEffect C++ class. AudioEffect is the base class for effect specific implementations,
OpenSL ES effect interfaces and audio effect JNI.

Added the AudioEffect JNI and AudioEffect JAVA class. AudioEffect is the base class
to implement more specific JAVA classes to control audio effects from JAVA applications.

Change-Id: If300a1b708f2e6605891261e67bfb4f8330a4624