[daip] IMERG, and now IMAGR

[Eric Greisen]

Oddly it did not have to do directly with the parameters although the 
lower default cutoffs would change things.  I found that an island in 
the list could get blanked out = (0,0,0,0) in making the list and the 
higher level routine never checked for this.  Then - only on 32-bit 
Linux Intel compiled - the reference to array(0,0) was outside the 
allocated memory and aborted.

A fix will arrive tomorrow.  Many thanks.

Eric