[mediacapture-depth] Pull Request: Fix #110, #135: Intrinsics and extrinsics

astojilj has just submitted a new pull request for 
https://github.com/w3c/mediacapture-depth:

== Fix #110, #135: Intrinsics and extrinsics ==
Aligned the existing (focal length) to Tango, Kinec2 and RealSense 
naming.

TODO: formulas for deprojection, distortion, projection and examples.

Fix #135: Focal length seems under defined
Fix #110: Accessing Camera Calibrations

See https://github.com/w3c/mediacapture-depth/pull/144