Changed makewcs to print a message and continue with the next file when a valid idc table is not found. It used to raise an Error and stop processing. Since it's used from pydrizzle now the previous behaviour would prevent pydrizzle from running with cubic coefficients.
Changed makewcs to print a message and continue with the next file when a valid idc table is not found. It used to raise an Error and stop processing. Since it's used from pydrizzle now the previous behaviour would prevent pydrizzle from running with cubic coefficients.

git-svn-id: e4aa3cfa51ba591d1cd1dbbaf7e4a2c2b5d7a7ff@1351 fe389314-cf27-0410-b35b-8c050e845b92

spacetelescope/stsci.tools