refs #8804 started cherry-picking from #7529

 Started new ConvertToMDHelper

which would use ConvertToMD core as the main part of the algorithm

Conflicts:
	Code/Mantid/Framework/MDAlgorithms/test/ConvertToQ3DdETest.h
refs #7529 Small further changes

(not in any way completed)
refs #8804  cherry-picking General framework for ConvertToMDHelper2

probably not yet working correctly

Conflicts:
	Code/Mantid/Framework/MDAlgorithms/inc/MantidMDAlgorithms/ConvertToMD.h
	Code/Mantid/Framework/MDAlgorithms/src/ConvertToMD.cpp
	Code/Mantid/Framework/MDAlgorithms/test/ConvertToMDComponentsTest.h
refs #8804 Get rid of test for ConvertToMDHelperParam

as the function has gone

cherry-picking

Conflicts:
	Code/Mantid/Framework/MDAlgorithms/test/ConvertToMDComponentsTest.h
refs #7529 Enabled "distribution" mode conversion for matrix workspace
refs #7529 Something working

but may be incorrect and properties are not copied correctly
refs #7529 All seems work except some tests

which can be incorrect with new changes.
refs #8804 Cherry-picking: All seems fixed

Conflicts:
	Code/Mantid/Framework/MDAlgorithms/test/ConvertToQ3DdETest.h
refs #7529 MAC is different ....
refs #7529 fixing typo
refs #8804 fixing compiler warnings on Nix

Conflicts:
	Code/Mantid/Framework/MDAlgorithms/src/ConvertToMDHelper2.cpp
refs #8804 A bit more wiki description.

Conflicts:
	Code/Mantid/Framework/MDAlgorithms/src/ConvertToMDHelper2.cpp
refs #8804 final bits of cherry-picking
refs #8804 finished separating ConvertToMDHelper2
refs #8804 Just some formatting
refs #8804 temporary disabling tests for ConvertToMDHelper2

As the algorithm will be rebuild anyway.
refs #8804 Temporary disabling unix warnings

(changes to the algorithm are due anyway)
refs #8804 Disabling 3 more failing tests
refs #8804 method returns the range of the X-values from ISpectrum
refs #8804 checkpoint, nothing finished yet.