The calibration parameter table that is generated when creating a new
calibration is now loaded back into mantid from the file as a table
workspace, rather then just working in the background.

Documentation has been added for the less obvious public and private methods.
Some of the methods in the model should be shown as private, so have
had methods refactored.

Vanadium corrections are used across the various
tabs, so the functionality is refactored out of the
calibration tab's model.