Updated ROMS plotting pakage

[arango]

I made couple of changes to Utility/opencdf.F to fix the problem of reporting the correct date if not using modified Julian day number. The logic was failing when have the time attribute in the Gregorian Calendar other than:

       units = seconds since 1968-05-23 00:00:00
or
       units = days since 1968-05-23 00:00:00

I also changed Utility/mskscl.F to have instead:

+      IF ((lmsk.gt.0).and.                                              &
           ((mskinp1.and.(ncid.eq.ncgrd)).or.                            &
      &     (mskinp2.and.(ncid.eq.ncid2)))) THEN

The logical flag lmask is internal to cntwkspa common block and has not been initialized yet. It is only used when drawing. We need to use lmsk instead to read the appropriate land/sea mask array for processing current field. Once that this was corrected, I was able to draw the ROMS grid mesh in masking applications.