Improvements for GenBank reader/writer.  - improved modelling of the GenBank item type. now supports any type of sequence as origin  - refactored parser  - replaced writer with a more generic function  - removed baseSpan search due to incomplete modelling
Improvements for GenBank reader/writer.
 - improved modelling of the GenBank item type. now supports any type of sequence as origin
 - refactored parser
 - replaced writer with a more generic function
 - removed baseSpan search due to incomplete modelling

CSBiology/BioFSharp,HLWeil/BioFSharp,bvenn/BioFSharp,bvenn/BioFSharp,HLWeil/BioFSharp,HLWeil/BioFSharp,CSBiology/BioFSharp,bvenn/BioFSharp,HLWeil/BioFSharp,muehlhaus/BioFSharp