ASACORE-1118 Fix for Objective-C AJNAboutObjectDescription unit test failure

The AboutObjectDescription test was failing due to multiple reasons
1. One variant of constructor was not accessing the wrapper C++ class
2. Dispatch queue mechanism in AJNAboutListener was releasing the variables
   used in the block which lead to corrupt object description arg being
   passed in annouce signal which lead to AboutObjDescription not being
   created correctly
3. AboutData arg also suffered from the problem of dispatch queue scoping
Also, changed the AJNAboutObjectDescription methods to take in NSString at
places it was taking char ** since it becomes tedious in Objective-C to use
malloc instead of NSString
Modified about client to reflect the changes
Added more tests for About Object description

Change-Id: Ie9753ea48f673246d8b076e4ebf981f8302f6fba
Signed-off-by: Nikhil Dabhade <ndabhade@qce.qualcomm.com>
Merge "ASACORE-1118 Fix for Objective-C AJNAboutObjectDescription unit test failure" into RB14.12