WaterMark: create water mark plugin

AudioFilter/ffmpeg/rules.mak

AudioFilter/main.cpp

AutoAnswer/main.cpp

GreenScreen/main.cpp

GreenScreen/videoSubscriber.cpp

HelloWorld/CenterCircleVideoSubscriber.cpp

HelloWorld/CoinCircleVideoSubscriber.cpp

HelloWorld/main.cpp

SDK/Templates/build.sh

SDK/Templates/main.cpp

SDK/Templates/preferences.json

SDK/Templates/videoUpdate.txt

TensorflowSegmentation/main.cpp

TensorflowSegmentation/videoSubscriber.cpp

WaterMark/CMakeLists.txt

WaterMark/WatermarkMediaHandler.cpp

WaterMark/WatermarkMediaHandler.h

WaterMark/WatermarkVideoSubscriber.cpp

WaterMark/WatermarkVideoSubscriber.h

WaterMark/build.sh