new module Bio::Tools::Alignment::Overview

Some time ago I made the mistake of uploading to CPAN a module called Bio::Tools::Alignment::Overview, the module wasn't associated to bioperl but for some reason I decided to use the namespace anyway (yeah, I know...)

Now I'm organizing some projects and I decided to include the module to bioperl, so if you accept this pull request I will remove from PAUSE/CPAN the current module, so that you can upload it under bioperl.

Sorry for the noobish mistake =)

Cheers.