implement multithreaded version of LTRharvest
update CHANGELOG
make LTRharvest output GFF3 on stdout for piping
make LTRharvest output seqids, optionally MD5 tagged
update CHANGELOG
remove dead code
remove test for missing .des table
enable threaded tests for LTRharvest
use regionmappings for LTRdigest
ensure sorting after seed extension
improve duplicate detection
streamline code
documentation
remove debug code
function naming
update CHANGELOG
only try to sort results when there are any
large rework of LTRharvest overlap handling