This commit add the option for the user to set the PDF output type on the polaris
create_total_scattering_pdf function. They can use any of the types available through
PDFFourierTransform (G(r), g(r), RDF(r)), if none given it will default to G(r).

Re #27607

Improves flexibility across instruments instead of writing
more code.
Refs #26639

Refs #21294

Refs #21294

Refs #21294

Merge to ensure CrystalFieldFunction is available and up to date.

Re #19921

The version of Pygments on RHEL seems to be case sensitive so
'Python' is not recognised as a valid lexer. Also fixed a few
reference errors.

Refs #10870

This reverts commit 14391c58.
refs #7284

refs #7284

Move mantidplot.py back up next to the executable to avoid the clunky
workaround and have a more obvious module name.