Uniprot annotation score for picking representatives and ordering/filtering alignments

The uniprot annotation score (http://www.uniprot.org/help/annotation_score) describes how complete the annotation is for a particular sequence. It is often useful to use this as a metric when:
* deciding which redundant sequences to remove (remove the least well annotated)
* selecting representative sequences (pick the most well annotated)

Additionally, a 'sort by' option can be provided to order sequences by their uniprot annotation score.