cal: Add legacy QA parameter file.

This may become a [Legacy] set of parameters within the standard
qa.ini.  This would need to overrule existing SURVEY headers so as to
pick the correct set.

For now use the calibration system to choose which QA parameter file
is required.  This does generate additional warnings.
cal: Offer a selection of the two QA parameter files via a legacy header.

This may be temporary if the legacy parameters can be incorporated into
qa.ini.  Saving this scheme for now as it works.

A simple $Cal->qaparams( "legacy_qaparams.ini" ) did not work.
heterodyne: Set and report Legacy QA parameter file.
heterodyne: Override the survey for the QA reports.
heterodyne: Report baseline order correctly.
heterodyne: Switch the survey to legacy when the LEGACY header is set.

This must be passed through to the _CREATE_NOISE_MAP_ primitive
to have LEGACY appear in the ORAC-DR log and qa.log, rather than any
original survey or Telescope (although currently Legacy and
Telescope/default QA parameters are the same).
heterodyne: Wrap long line in prologue.