fileset: treat encoding and eol as the predicate calling _existing
Before this patch, predicate function 'encoding' and 'eol' aren't
listed up in '_existingcallers', even though they invoke 'existing()'.
This causes unexpected failure of these predicate, if there is a
(manually) deleted file in the working directory.
8a0513bf030a and 3ce3f2b059a1 seem to overlook putting already
existing 'encoding' or newly introduced 'eol' into '_existingcallers'.
This patch also changes order of fileset "eol(unix)" output in test,
because "existing caller" predicates show "A(dded)" files before
"C(lean)" ones.