NAME:
  stageselect
 PURPOSE:
  Selects catalog stars for a given RA/Dec range.
 DESCRIPTION:
 CATEGORY:
  Photometry
 CALLING SEQUENCE:
  stageselect,minra,maxra,mindec,maxdec, $
                ra,dec,rasig,decsig,b,bsig,v,vsig,bmv,bmvsig,nstars
 INPUTS:
  minra - lower Right Ascension constraint (radians)
  maxra - upper Right Ascension constraint (radians)
  mindec - lower Declination constraint (radians)
  maxdec - upper Declination constraint (radians)
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
 OUTPUTS:
  ra     - array containing RAs of standards within limits, J2000, radians
  dec    - array containing Decs of standards within limits, J2000, radians
  rasig  - array of uncertainties of RAs (arcsec)
  decsig - array of uncertainties of Decs (arcsec)
  b      - array of B magnitudes of standards
  bsig   - array of uncertainties of B magnitudes
  v      - array of V magnitudes of standards
  vsig   - array of uncertainties of V magnitudes
  bmv    - array of colors of standards
  bmvsig - array of uncertainties of colors
  nstars - number of stars returned
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
  This gets its data from the phot.plphot database table.
 PROCEDURES:
 MODIFICATION HISTORY:
  2012/03/06 Written by Erin R. George, Southwest Research Institute
  2012/12/06, MWB, added nstars return and some cosmetic cleanup