Represent a Sequence Feature holding info about a part of a sequence.

This is heavily modeled after the Biocorba SeqFeature objects, and may be pretty biased towards GenBank stuff since I'm writing it for the GenBank parser output...

What's here:

Base class to hold a Feature. ---------------------------- classes: o SeqFeature

Hold information about a Reference. ----------------------------------

This is an attempt to create a General class to hold Reference type information.

classes: o Reference

Specify locations of a feature on a Sequence. ---------------------------------------------

This aims to handle, in Ewan's words, the dreaded fuzziness issue in much the same way as Biocorba. This has the advantages of allowing us to handle fuzzy stuff in case anyone needs it, and also be compatible with Biocorba.

classes: o FeatureLocation - Specify the start and end location of a feature.

• ExactPosition - Specify the position as being exact. o WithinPosition - Specify a position occuring within some range. o BetweenPosition - Specify a position occuring between a range. o BeforePosition - Specify the position as being found before some base. o AfterPosition - Specify the position as being found after some base.