Sorting out whitespace. Sorry cannot read the file without this change
[ENSCORESW-809]. Bugfix for 1bp CDS exons missing from dump.

Seems that some odd logic meant that very short CDS exons were missed
from the GTF dump and not printed. Solution is to add a test to
see if the exon was less than 3bp long assuming it’s an issue with
stop codon detection.
Support the fetching of Selenocysteine edits alone for GTF dumper
[ENSCORESW-807]. Supporting new dump formats.

GTF now supports dumping of UTRs, selenocysteine edits and CCDS
cross references. We also dump the assembly version to the header of the
file. This brings us closer in line with Gencode.
Now encodes UTRs correctly and adds more meta data.

Also the read me has been updated accordingly as have the test cases.
do not sort utrs
Adding the new attributes for showing a lack of detected cds and mrna end
Merge branch 'experimental/fixgtfdumper'

Introducing a new version of our GTF dumper. Now supports
gene and transcript features, seleno markup, ccds xrefs and
a new readme.