Merge pull request #20 from stereolabs/feat_depth_tapi

Feat depth tapi

Update defines.hpp

Update changelog.md

Update changelog.md

Update changelog.md

Fix doc and code improvements (#3)

* Improved documentation
* Add missing README image
* Add missing doc files
* Doc refactoring
* Add `video` namespace
* Add `sensors` namespace
* Add `sensors::data` namespace
*Sensors Data names refactoring
* Add doxyfile
* Update doxygen.yml
* New "sensors::usb" namespace
* Update changelog.md
* Update defines.hpp
* Update changelog.md
* Fix downloading calibration file
* Fix calibration file downloading on Ubuntu 20.04
* Minor fixes
* Compilation flag to reduce final size of the library
* Compile flag changed to O2 to improve performances
* Changed returned data type from pointers to references
* Minor fixes to video examples
* Improved sensors data validity info

* Doc minor fixes

* Change default resolutions for examples