Add rapidjson license.txt file to external.
Add rapidjson license.txt file to external.

wrld3d/wrld-example-app,wrld3d/wrld-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app