refs #9581 PDFFourierTransform description and usage sample
refs #9581 Intermediate changes to ConvertToMD&related documentation
refs #9581 ConvertToMD limits
refs #9581 Parts of ConvertToMD
refs #9581 ConvertToMD tests and docs
refs #9581 PreprocessDetectorsToMD documentation and test samples
refs #9581 conflicts with develop (probably due to untested tickets)

Merge branch 'feature/9581_SphinxChanges' into develop

Conflicts:
	Code/Mantid/Framework/MDAlgorithms/src/ConvertToMDParent.cpp