[Biopython] MetaGene and GreenGene

[Kyle Ellrott]

I've added two modules, MetaGene and GreenGene, to my BioPython fork.
(found at http://github.com/kellrott/biopython/ ) Both of these
modules deal with tools/databases related to metagenomic research.
The GreenGene module parses and stores the 16S RNA sample library
found in the file at
http://greengenes.lbl.gov/Download/Sequence_Data/Greengenes_format/greengenes16SrRNAgenes.txt.gz
and provides a query mechanism to lookup sequence and studies.
MetaGene parses output from MetaGeneAnnotator (
http://metagene.cb.k.u-tokyo.ac.jp/metagene/ ), a gene prediction
program designed for prokaryote and phage.  It takes the predictions
and produces SeqRecord objects of the predicted Amino Acid sequences.

I would appreciate comments on additional functionality people would
find usefully for these packages.  I would also request these modules
be considered for the mainline BioPython distribution.

Kyle