Changed example readme format for asset store compatibility

HoloLensVideoCaptureExample/Assets/CamStream/README.txt

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+The most up-to-date documentation is available on GitHub: https://github.com/VulcanTechnologies/HoloLensCameraStream
+
 # HoloLensCameraStream for Unity
 This Unity plugin makes the HoloLens video camera frames available to a Unity app in real time. This enables Unity devs to easily use the HoloLens camera for computer vision (or anything they want).