changes necessary for performing a Beam tomography

[amereghe]

This PR is a follow up of PR #58
Some functions are follow ups of what developed in https://github.com/amereghe/GuessBeam

Major changes:

• adding a function showing main optics functions at an element during a scan;
• possibility to read .tfs tables listing currents in scans and survivors/lost particles by MADX/PTC tracking engines;
• adding functions to read/write MADX/PTC starting conditions;
• adding a function to convert bin centres to edges;
• plotting sinograms (also with a 3D visualisation of the the histograms ensamble); spectra can be show as 3D sinograms;
• possibility to compare multiple sets of spectra one by one;
• adding a function to convert .xlsx files for QA into .tfs tables;
• possibility to create elliptical or rectangular contours to phase space plots, either based on optics functions / parameters or statistical analysis of the beam enemble;
• adding a function to sample a beam population and another one for normalising coordinates;
• adding functions to compute beam statistics and showing it;
• considering also CO in stat analisis of a beam sample;
• When solving system of linear equations to get beam size or position, no longer use linsolve but lsqminnorm, such that (in case of non-unique solutions) the solution with min module is chosen.

Minor changes:

• CompareOptics.m: phase advances can be compared;
• DisplayBeamProfiles.m: when showing spectra, the user decides wether to use energy or range or IDs of profiles as independent variable;
• PlotLattice.m: the function auto-detects if s-coordinate is given at the centre of the elements or at the end;
• PlotLossMap.m: indices can be omitted from interface;
• ScatterPlot.m: indices can be omitted from interface and possibility to receive data as a cell array or as a matrix;
• ShowLossMap.m: indices can be omitted from interface.