Rename QJNIXxx classes to QAndroidJniXxx.

The old classes where not following the usual convention for acronyms
in class names.

Change-Id: I2fad72483c51ca95a2703d914d6a678c5f7cde98
Reviewed-by: Jake Petroules <jake.petroules@petroules.com>
Reviewed-by: Yoann Lopes <yoann.lopes@digia.com>