Make the error locations fine-grained, particularly so they point to
individual fields, not the whole match.
-(10) Cross-module, persistent, named patterns, see:
+(10) DONE - Cross-module, persistent, named patterns, see:
http://caml.inria.fr/pub/ml-archives/caml-list/2008/04/25992c9c9fa999fe1d35d961dd9917a2.en.html
(11) DONE -
(12) DONE - More constant field lengths.
-(13) Implement native endian functions.
+(13) PARTLY DONE - Implement native endian functions.
(14) PARTLY DONE - A proper test suite.