ZBarFilter: Add c++ implementation

Change-Id: I6a6106d08cdf4f2619c2595bcb258021fbad2171
GStreamerFilter: Add c+ implementation

Change-Id: I0670e583e76bdfa3410309d87b70a1c120b26f79
FaceOverlayFilter: Add c++ implementation

Change-Id: I015e69aa3987f9705a74b42d59be7139e21e1830