Tango RGBD image grabber

This was a memo to a coworker at Microsoft

Here is the code for the Tango app I made. 

1.	My code is based on https://github.com/googlesamples/tango-examples-c, which is the official sample apps for C.
So this is pretty well managed and has a detailed guide on how to install the sample apps, for example: https://developers.google.com/tango/apis/c/

2.	If you can get their sample apps work first, then you can grab my changes to output the images as files
https://github.com/Efreeto/tango-examples-c/tree/woki is a fork of the above code.
I tested it’s working, and its final version is with the phone.

3.	In case you are having troubles, you can try reverting some of my changes. Here are all the changes I made from the original: https://github.com/googlesamples/tango-examples-c/compare/master...Efreeto:woki

We’ve discussed about some potential improvements, but I couldn’t make them.
•	I’ve looked hard for this, but I concluded there is no simple instruction to output depths as floating points. However, TangoPointCloud structure does provide float[4] where {X, Y, Z} is a coordinate triplet (in meters). C is a confidence value, in the range of [0, 1], but it’s in 3D, not 2D. This structure is easily available in this code.
•	Adding to above, as I’ve said before, point cloud projection is done on OpenGL level internally.
•	Another approach would be scaling the 0-255 in the current image to some other range. 0.5m to 4m is the official range of the tango camera, so maybe you could start from here.
•	Taking pictures horizontally is easy. Just tilt the phone. The app supports 90, 180, 270, 0 degree changes.
•	Intrinsic camera parameters are provided by TangoCameraIntrinsics. This is also easily available in the app.