PICARD: initial JSA catalogue recipe
JSA: jsa catalogue recipe now produces preview images.

Separate pngs for each clump and the peak catalogue are created
and will need to be merged.
JSA: tidying up of primitive
JSA: JSA catalog preview images
JSA: jsa cat primitives now work on blank maps.
JSA: catalog preview images now separate for peak and extent

Should work when no catalogs were detected. Minor fix to documentation
included.
JSA: jsacatalogs have more sensible column names.

Also fixed some bugs. Note that this is using some rather
horrible stilts commands to fix up some column names, and this
is going to be updated in the jsacat option for cupid findclumps/
extractclumps asap.
JSA: allow use of JSA tile naming in catalog recipe

Most of the JSA_CATALOGUE recipe has been moved to a primitive
_CREATE_JSA_CATALOGS_ in order to allow it to set up suitable
frame and group classes.  This is required in order to allow us
to use JSA methods such as inout_jsatile and jsa_pub_asn_id.

Also changed from running the primitives "in frame mode" to running
them "in group mode" because we need the "group mode" kind of headers
in order to be able put the catalogs in the "public" category
(instead of "obs") of the JSA.

The change to the classes prevents FITS files from being added
to the object, so the FITS catalog file names have to be
recorded in the uhdr instead.
JSA: correcting JSA cat parameters
general: improvements for clump and catalog previews

This improves the command to plot the clumps, and attempts
to use image magick convert to stick the images together.
TODO: we need a better means of detecting where 'convert'
lives.
JSA and general: improvements to jsa catalog pngs.

_CREATE_GRAPHIC_FROM_FILE_ now supports low and high sigma
values for plotting the map, and will plot the clumpoutlines and
the catalog positions on the catalog map if given both.
JSA: copy JSA FITS headers to catalogs

Since the catalogs are now created in suitable JSA group, the
_COPY_JSA_HEADERS_TO_FITS_FILE_ primitive no longer needs to create
temporary frame and group objects.
JSA: set product ID prefix for extent and peak

The extent plane will contain multiple products, so construction
of the product ID by appending the subsystem to the product is
unsuitable in this case.  Since access to the product-overriding
argument of the product_id method is not always available, (e.g.
when that method is called by collate_headers), it appears that it
is necessary to be able to store a product ID prefix separately from
the product name in the object.  The extent and peak catalog
creation primitives now set the product ID prefix in the object
and unset it again before they complete.  Additionally collate_headers
must no longer attempt to force the product part of the product ID
to be the value returned by the product method because the product_id
method already falls back to the product method so it isn't necessary,
and when it does do so it prevents the product_id method from making
use of the new product ID prefix setting.
JSA: correct product ID prefix in comment
JSA: no longer assume group mode for FITS headers
JSA: create MOC files for the tile and islands
JSA: ensure tempfiles are removed in jsacat
PICARD: do not list PNG files for keeping

_DELETE_TEMP_FILES_ only checks the frame / group intermediates,
so it is not necessary to ask it to keep PNG files.
JSA: add -cat suffix to names of FITS catalogs

The "suffix" part of the filename for the FITS catalogs
is now peak-cat or extent-cat.
JSA: tag as "representative" the extent-mask file

Now create the clump assignment file (a.k.a. "mask") with a temporary
name ("mask") and then use _TAG_AS_REPRESENTATIVE_ to make a copy called
"extent-mask" with the product headers set appropriately.

_TAG_AS_REPRESENTATIVE_ now uses inout_jsatile if JSA_TILES is set,
and uses the product ID suffix if present rather than the product
name when generating the product ID.

Note: _TAG_AS_REPRESENTATIVE_ currently makes an unnecessary preview
image based on the clump assignment file.