Fix typos in py_houghlines tutorial.

- disabled OPTIMIZE_OUTPUT_JAVA
- filtered out *.m scripts
- removed link to old Sphinx documentation
- replaced all mentions of Sphinx with Doxygen

Fix tutorial code link in basic_linear_transform tutorial.

hal_internal.cpp(101): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data

- added compile check with multiple tries for different configurations
- restored find_package(LAPACK)
- avoided modification of OPENCV_LINKER_LIBS

ml: fix small typo in lr.cpp (#8019)

Fix error usage in HitMiss tutorial, and improved the visualization results (#7978)

* Fix error usage in HitMiss tutorial, and improved the visualization results

Fix error usage in HitMiss tutorial, and improved the visualization results

* Update HitMiss.cpp

* Update HitMiss.cpp

Fixed exceptions, print statements, and long types for gen_pattern.py to be Python 3 compatible (#7994)

* fixed exceptions and print statements to be python 3 compatible; removed long type checks (py3 uses int); whitespace reformatting

* Pulled latest svgfig from upstream

https://github.com/jpivarski/svgfig/commit/f3179a8926508bf0f9021fd4e1f9731c95524a38

 - add v_popcount in universal intrinsic
 - add test for v_popcount
 - add wrapper of popcount for both MSVC and GCC

Add OpenCV parallel_for_ tutorial.