SCUBA2: add a sensible default for IMAGE

If no input image is given, then it should be safe to assume that the
current Frm or Grp file can be used. Add the GROUP argument to define
the current object.
SCUBA2: use new input arguments to control processing

Now this primitive uses the files in the current frame object with the
option of specifying a SMURF extension (via the new SMURF argument),
e.g. "nep" to mosaic the NEP data. The output mosaic has a suffix
given by the new SUFFIX parameter and is stored in the Frame at the
end of processing. The file is tagged with the given suffix.

The INFILES and OUT parameters have been removed.
SCUBA2: updates to use tags, new names for displayed files

The new interface to _MAKE_MOSAIC_FPLANE_ is used along with a number
of tags for easy intermediate file storage and retrieval, replacing
the use of temporary Frame objects.

The responsivity plots are now created from separate files (rather
than NDF components within a single file) which requires an
accompanying update to disp.dat.
scuba2: new names for responsivity plots

Instead of mulitple NDFs within a single file, the new and old
responsiviity mosaics are now separate files on disk with new
suffices. The percentage change image also has a new suffix
(respdelta).
SCUBA2: use tags for easy file storage/retrieval

Use the new interface to _MAKE_MOSAIC_FPLANE_, and use tags for easy
storage and retrieval of files.

Tweaks to user feedback and setting the histogram plot limits.
SCUBA2: keep responsivity mosaic on disk

Add the _respmos file to the list to keep.
SCUBA2: tag and define a product for the calibrated data

The tag and product name is "calib". The primitive checks if a
calibrated product already exists for the current object and if so,
will not re-apply a calibration factor.
SCUBA2: tag and store matched-filtered output as a named product

The product is defined as "Matched-filtered" and is used to check the
input data so that the filter is not applied twice. The output file is
tagged (using the simpler name "matchfilt") so it can be used by
subsequent primitives.

The OUT, OBSEND and STORE arguments have been removed - the filtered
input map is now stored in the current Frame or Group object (as
defined by the GROUP parameter). Similarly, the inout method for the
current object is used to define the name of the filtered map.

A check has been added for the case when the user supplies a PSF that
the pixel scale matches that of the input file.
SCUBA2: input Frm/Grp must now contain the data and model

The IMAGE and MODEL input parameters have been removed so that the
input Frame or Group (determined by the GROUP parameter) must contain
two files: the data and the model fit. These files are retrieved using
the tag "profile_fit".

A check is made to see if the current product for the input object
indicates matched-filtered data so that corresponding plot titles can
be set and the data are plotted correctly.
SCUBA2: store new map as makemap product

And tag it as "newimage".
SCUBA2: tag new group coadd and store as "coadd" product

The new Group file is stored in the object as a "coadd" product and
tagged with the same.

The makemos code has been moved to a more suitable location.
SCUBA2: allow both Frame and Group objects to be used

Previously only the group object was queried for its file. The GROUP
parameter now does what it does in many other primitives.
SCUBA2: use tags for retrieving and storing useful files

Also always use the current object for all methods (rather than only
using Frm in some cases).

The MF input parameter has been deleted. The primitive now checks to
see if matched-filtered data exist in the current object.

On exit the object is returned to its entry state (tag and product).
SCUBA2: use tags for using/storing files

Use tags and product names rather than setting special uhdr values
and/or defining in/out file names.

Update calls to other primitives to reflect changes in their API.

The input object is restored to its entry state on exit.
SCUBA2: calculate SNR image for whatever is in given object

Now this primitive simply calculates an SNR image for the file in the
specified object. If the user wishes that to be the output from the
matched filter then they must set the input file accordingly.

Output data are tagged with "snr" (same as product name) and is always
updated.

The SNRMAP uhdr has been removed as the tag serves the same purpose
but in a better way.
SCUBA2: use tags to retrieve files

This primitive also assumes that there is only a single file in the
current Frame (this is a Frame-based primitive only). The operation is
carried out on the file tagged with "newimage" provided that it is not
calibrated.
SCUBA2: use GROUP to specify input file rather than IMAGE

As part of a general API tidy up, the use of IN or IMAGE as input
parameters is being phased out where possible.

And sigma should be NaN rather than left undef if bad.
SCUBA2: retrieve data tagged with snr or matchfilt as appropriate

If a SNR image already exists, then source finding is carried out on
that image. If not, a SNR image is calculated, the input to which is a
matched-filtered map if one exists.

And rely on default image choices where possible depending on GROUP
input parameter.
SCUBA2: use tags for retrieving/storing data

Rather than mess about with uhdr flags, tags are created for each
focus position, all of the images to go into the cube, the midplane
image (used for determining the source position before shifting the
WCS) and the final output cube. The cube is also stored as the product
"focus_cube". Another feature of this is the replacement of temporary
files with named intermediates to aid with debugging.

On exit, the Frame object is restored to its entry state (the focus
cube is a Group product).

One last update is that the sky mapping is now only retrieved once.
SCUBA2: check for focus_cube product

Use the named product rather than a uhdr flag.