[BioRuby] BioRuby Tutorial (en)

[Pjotr Prins]

Noticing the increasing interest for BioRuby and in preparation for
the BioHackathlon I have fixed the Tutorial.rd.en at:

http://dev.bioruby.org/wiki/en/?Tutorial.rd

Please have a look and see if the contained information is still
valid. If you think anything is missing, or could be done easier,
please send me a note too.

Thanks,

Pj.