Merge pull request #21 from jonathancrabtree/master

Improved option handling
Added full serialization support for UTR features
Merge branch 'master' of github.com:jorvis/biocode
Now checks and reports an error if an mRNA is found without any CDS children
Changed python3.2 in shebang to just python3
Renamed structural_comparison_gff3.py to compare_gene_structures.py
minor: added attribution since a bug was filed.
Added total/empty molecule length reporting
Now counts the area from molecule ends until the nearest gene as intergenic space (per SO definition)
Critical fix for GFF3 parser to ignore non-FASTA directive comment lines