Bio::Coordinate modules ready for use

Generic and gene-specific coordinate system mappers are ready for use.
These modules can ease the pain of mapping sequence features from one sequence coordinate to other ones, e.g. from cds to genomic and chromosomal.

See the announcement at

Code and documentation updates were finished at the Singapore BioHackathon. The fixes will be part of the upcoming 1.2.1 bioperl release.