Doxygen tutorials: some fixes in RST-docs
Doxygen tutorials: basic structure
Doxygen tutorials: warnings cleared
Doxygen tutorials: cpp done
Doxygen tutorials: python basic
Doxygen tutorials: python final edits
User guide converted to doxygen
Doxygen tutorials: support contrib, some minor changes
Documentation: removed mention of Mat(IplImage*) constructor
Fixed whitespace warnings in new tutorials
Merge pull request #3479 from mshabunin:doxygen-tutorials