Must have that flag. Otherwise following "doxygen overview" tutorial won't work.

* Fix Issue 13908

Allocate the matrix _Jo only when the solver needs it (ie when solver.state == CvLevMarq::CALC_J)

* Fix calib3D unit test

Fix _Jo allocation when stddev is not empty

* Removing trailing whitespaces

* scope _dp* variables

* fix whitespaces

- V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT
- V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH

* Android build improvements
* look for NDK in "ndk-bundle" directory under the SDK directory if location not specified
* look for cmake and ninja in "cmake" directory under the SDK directory if not found in the path
* disable use of ccache if not found in the path

* Redo build tool existence checks

* core, stitching: revise syntax to support Visual C++ 2013

* stitching: revise syntax again to support Visual C++ 2013 and other compilers

* stitching: minor update to clarify changes

- support comma-separated list in VIDEOIO_PLUGIN_LIST
- opencv tests/samples depend on plugins virtual target

declaration order is not fixed

Error message:
Core.java:97: error: illegal forward reference
    Hamming_normType = NORM_HAMMING,

- better handling of enum arguments
- less merge conflicts