Add algorithm to normalise compton scattering spectrum by hydrogen peak area

[martyngigg]

This will require two new algorithms:

1. ConvertToYSpace -

The required conversion is defined by equation (7) in this paper:
http://link.aip.org/link/doi/10.1063/1.3561493?ver=pdfcov. As the mass & detector delay time are required to calculate Y we cannot simply add a new unit for ConvertUnits. The algorithm will have a single input, the mass and all other parameters: l1,l2,theta,efixed,t0 will be required to be attached to the workspace instrument.

1. NormaliseByPeakArea -

This will use the above algorithm to convert the input TOF spectrum to yspace & then Fit the peak defined by the input mass value. The input data will then be normalised by the fitted peak area value.

[martyngigg]

This issue was originally trac ticket 8598

[martyngigg]

http://trac.mantidproject.org/mantid/raw-attachment/ticket/8598/HydrogenPeakFit.jpg

(uploaded by @martyngigg on 2014-01-08T11:20:09)

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