NAME:
    itool_pplod
 PURPOSE: (one line)
    Load itool photometry parameters from a file.
 DESCRIPTION:

 CATEGORY:
    Widgets
 CALLING SEQUENCE:
    itool_pplod, ph_parms
 INPUTS:
    ph_parms : The photometry parameters structure (See itool.pro).
 OPTIONAL INPUT PARAMETERS:

 KEYWORD PARAMETERS:
    ERROR_STR    = A string variable in which an error string may be returned.
                   A null string is returned, if no errors were encountered.

 OUTPUTS:

 COMMON BLOCKS:

 SIDE EFFECTS:

 RESTRICTIONS:

 PROCEDURE:

 MODIFICATION HISTORY:
    2004, Apr, DWL. Adapted from it_pplod.pro. Added some GUI message
 dialogs.
    2006/5/22,  Peter L. Collins, Lowell Observatory.
               Added CCD readout noise parameter (rdnoise).