Modified tube_calib.py accordingly re #6344

Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>
Enable ApplyCalibration.cpp to handle MAPS re #6344

Also first step towards handling tubes of arbitrary orientation.

Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>
Enable Calibration to Continue after bad tube re #6344

Previously calibration would stop if a tube were found for which the spectra could not be obtained. Now it skips that tube a calibrates subsequent tubes.

Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>
Enable graph of one tube to be plotted re #6344

Graph is not actually plotted by the script, but its workspace is saved to enable plotting after running the script.
Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>
Add *.nxs as a filetype & make error message less misleading re #6499

Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>