libfreenect2: Add new libfreenect2 package.

[sh0]

Specify library name and version: libfreenect2/0.2.1

The libfreenect2 library is used to communicate with Microsoft Kinect 2 devices.

Note that this library is completely different from libfreenect in PR #7627 and has its own versioning. Hence a separate package.

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[sh0]

From the test package it seems freenect2_INCLUDE_DIRS, freenect2_INCLUDE_DIR and freenect2_LIBRARIES are created in Findfreenect2.cmake so we probably don't need extra variables. It only works with cmake_find_package, but that is also the style of upstream CMake files so we should be fine now.

[madebr]

From the test package it seems freenect2_INCLUDE_DIRS, freenect2_INCLUDE_DIR and freenect2_LIBRARIES are created in Findfreenect2.cmake so we probably don't need extra variables. It only works with cmake_find_package, but that is also the style of upstream CMake files so we should be fine now.

I"m unsure how this will work in conan 2.0 when cmake_find_package and cmake_find_package_multi are deprecated.
But I guess that's thoughts for later.

[conan-center-bot]

All green in build 7 (6f83c63cf5bf63ccdf6cf46b32633d0880983605):

• libfreenect2/0.2.1@:
  All packages built successfully! (All logs)

[uilianries]

LGTM