Merge remote-tracking branch 'origin/feature/9128_hfir_reduction_flowchart'

Code/Mantid/docs/source/algorithms/HFIRSANSReduction-v1.rst

Code/Mantid/docs/source/algorithms/SANSReduction-v1.rst

Code/Mantid/docs/source/images/HFIRSANSReduction.png

Code/Mantid/docs/source/images/HFIRSANSReduction.xml

Code/Mantid/docs/source/images/SANSReduction.png

Code/Mantid/docs/source/images/SANSReduction.xml