Initial version of the model. Currently missing the plotting, file creation, and file system interaction.

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

The observer pattern is not Muon specific and could be used elsewhere. Moving it to somewhere not related to the muon GUI reduces the chance of the code being duplicated.

on MARI. Unit test for this axis. Also enabled unit tests for fast corrections despite the algorithms clearly return invalid result.

when no key algorithm selection key is present in the input dictionary

Updates ISIS SANS call count to reflect the lower number of calls to the
update method

Fixes a call which was clearning and repopulating the entire table for
batch data in the ISIS SANS GUI. Instead we now skip notifying until all
entries have been added so that the table refresh happens once

for the whole workspace

when returning a workspace pointer

anywhere

as it does not work in Direct mode

and minor bugs identified from testing

and their speed

all IDF modified to accept new properties as part of the reduction