[ Issue 1292 ] Fixed.

Arguments *ending* in data qualify for structural descent (in
--without-K), not only data arguments.
[ Issue 1292 ] Test case.
[ Issue 1292 ] Size also qualifies for structural descent.
[ Issue 1292 ] Test case for Size-recursion --without-K.
[ Issue 1023 ] test case was missing.
[ Issue 1023 ] Test case for coinduction.
[ Issue 1023 ] CHANGELOG (should have been in 2.4.2).