[services] Bug 439495: Thread-safe access to anonymous ID file.

Change-Id: I135c13ea2d097189f8c66abeaecaf7092ad5a294
Signed-off-by: Yasser Aziza <yasser.aziza@gmail.com>
Turn the anonymousId calss into an osgi service

Signed-off-by: Yasser Aziza <yasser.aziza@gmail.com>