This module reports errors from the perspective of the caller of a
"clan" of modules, similar to "Carp.pm" itself. But instead of giving
it a number of levels to skip on the calling stack, you give it a
pattern to characterize the package names of the "clan" of modules that
should never be blamed for errors. It makes these modules stick
together like a "clan" and any error that occurs will be blamed on the
"outsider" script or modules not belonging to this "clan".