Perl6-Signature

Alpha release - everything here is subject to change

Perl6::Signature models routine signatures as specified in Synopsis
6 of the Perl 6 documentation. These signatures offer a rich language
for expressing type constraints, default values, and the optionality
(among other things) of routine parameters.

Included is a parser for the Signature language, accessors and convenience
methods for querying Signature objects, and a pretty-printer for producing
their canonical textual representation.

