* pmObjects.c:

  - changed psModel.params & psModel.dparams to psVector
  - adjusted pmModelAlloc to match
  - added default to source->type (pmSourceAlloc)
  - changed return value for pmFindImagePeaks to psArray from psList
  - changed MyListAddPeak to reflect change to psArray
  - fixed error in pmFindImagePeaks:
    tmpRow = p_psGetRowVectorFromImage((psImage *) image, row);
    changed '0' to 'row'
    NOTE: also fixed by George
  - added pmPeaksSubset to replace pmCullPeaks: returns a new array
    with a subset of the peaks.
  - added tests in pmSourceLocalSky to keep subimage on main image
    NOTE: also fixed by George
  - CheckRadius2 seems inefficient, but I did not change it 
    (function should be inlined; we should store and compare against 
    radius2, not radius)
    NOTE: looks like these were changed to macros
  - added code to pmSourceMoments to do the second-order moments in
    two passes rather than one, but since it made no impact, it is
    ifdef'ed out.
  - forced the Sx,Sy values in pmSourceMoments to bottom-out at 0.0
  - added pmComparePeakAscend and pmComparePeakDescend functions
    (used by pmSourceRoughClass)
  - implemented the pmSourceRoughClass as I envisioned it
  - added tests in pmSourceSetPixelCircle to keep subimage on main image
  - fixed definitions of radius in pmSourceSetPixelsCircle
    NOTE: also fixed by George
  - inverted meaning of mask in pmSourceSetPixelsCircle
    (0 - valid, 1 - invalid)
  - changed source->models->params to vectors in pmSourceModelGuess,
  - changed source->models->params to vectors in evalModel
  - evalModel declared static
  - findValue declared static
  - modified default TOLERANCE, NUM_ITERATIONS in pmSourceFitModel
  - added the yErr entry to the model fit
    (yErr is currently set approximately -- needs GAIN & RDNOISE)  
  - changed the psMinimizeLMChi2 calls to work with the psF64 versions
    of the models rather than the _Vec versions (to match the API for
    psMinimizeLMChi2)
  - added elements nDOF and nIter to pmModel
  - set nDOF and nIter after fit result

  * for all of the models:
  - dropped the input checking for speed 
    (allow for #ifdef in/out?)
    (these functions are only called by psMinimizeLMChi2, so should already be valid)
  - dropped the _Vec versions of the model functions
  - changed return type of scalar versions of functions to psF64
    (allows the cast of psMinimizeLMChi2Func to be dropped in
    pmSourceFit)