v1.4.1: Minor bug fixes for 'empty' contig handling and StORF filtering

This minor update includes two fixes

• As highlighted by @LucyDillon in issue #4, StORF-Reporter was falling over when presented with an input contig WITHOUT any previous annotation. This was caused by the fact that CDS etc annotations presented to StORF-Reporter are used as anchors in the 'StORF-Filler' function which fits StORFs in the correct order in the new computed GFF file.
• There was a small issue with how some StORFs were filtered on opposite strands. That is now fixed and should results in less spurious StORFs being reported.