Repatch (from linux) of OSX IRAF

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+The apphot and daophot package aperture photometry tasks have been modified
+to compute the aperture sums and areas in double precision instead of real
+precision.  This change minimizes machine precision errors that can become
+significant for large apertures and very low noise or synthetic data.
+
+These tasks have also been modified to output negative values of the total
+flux should they occur. Formerly these values were being artificially set to 
+0.0. This change makes it easier to see the effects of any sky value and machine
+errors.
+
+The modified apertures photometry tasks are available under irafx. Let me
+know if you have any questions about the modified tasks or encounter and
+problems using them.
+
+
+					      Lindsey Davis
+					      davis@noao.edu