removed contrib, legacy and softcsscade modules; removed latentsvm and datamatrix detector from objdetect. removed haartraining and sft apps.
some of the stuff will be moved to opencv_contrib module.
in order to make this PR pass buildbot, please, comment off opencv_legacy, opencv_contrib and opencv_softcascade test runs.

update help corresponding single format and update some samples through using CommandLineParser class

improved tree_engine.cpp sample (added train file data specification; print sorted variable importance table)