PICARD: rename to indicate it just calculates the noise now
PICARD: modify primitive to use SCUBA2 image noise primitive

This primitive now just calculates the noise using the SCUBA-2
primitive _CALC_IMAGE_NOISE_. The same methods used by that primitive
are supported and may be specified by the recipe parameter NOISE_METHOD.

The result is stored in the PICARD_RESULTS uhdr hash reference as "noise".
PICARD: add NOISE_METHOD parameter for image noise estimates
SCUBA2: use file_exists method to check if file exists

Remove support for LOGFILE recipe parameter as it is not used anywhere.
PICARD: new primitive to apply calibration to SCUBA-2 data
PICARD: new primitive to calculate beam size from SCUBA-2 map
SCUBA2: add ability to specify FCF as an argument

This is not something the pipeline will do but it does allow the
primitive to be used by PICARD with resorting to index files. (This is
on the understanding that fewer output files is a good thing with
PICARD.)
SCUBA2: store the derived fluxes in the primitive hash under FLUXES

Another PICARD-driven upgrade - allow this primitive to return the
measured peak and integrated fluxes (and their errors) to a calling
primitive.
PICARD: change in names of FCFs stored in PICARD_RESULTS

And store the fluxes as determined during the FCF calculations.
PICARD: tidy up and refactor slightly to add new parameter
PICARD: factor out calibration into new primitive

The primitive now looks for data tagged with "calib" before
proceeding, and if it doesn't find any then it performs its own
calibration.
PICARD: rename to follow new recipe name

FCFNEFD is deprecated; it should now be CHECKCAL.
PICARD: major updates to reflect new output requirements

See SCUBA-2 Trac ticket #1178.
PICARD: rename to better reflect what this recipe should be used for

The old FCFNEFD recipe was cobbled together during commissioning and
was never a coherent piece of work. With the upcoming Starlink release
and data redeuction workshop, a new improved version was required that
could be used by observers to investigate the state of the calibration
observations obtained on the same night as their data. Behold,
SCUBA2_CHECK_CAL - perform checks on calibrator data.
PICARD: update to reflect new workflow

The old workflow from SCUBA2_FCFNEFD has been streamlined into a new
recipe with a more clearly-defined data processing path.
Calib::SCUBA2: new methods for handling fwhm and error beam

The results of a beam calculation are stored in the calibration object
in the hash reference BeamPar. Unfortunately, retrieving those beam
parameters requires unpacking the hash reference by the user, so two
new methods have been added to provide direct access to the latest
values of the FWHM and the error beam contribution.

Both of these are now calculated automatically if the beampar method
returns a valid result, and are updated at the time new beam
parameters are stored.