ensure consistent sorting in LTRharvest
gtlua: add GenomeNode:(get_)direct_children()
extend test cases
Merge pull request #390 from satta/ltrharvest_sorting

ensure consistent sorting in LTRharvest
Merge pull request #391 from satta/direct_children

gtlua: add GenomeNode:(get_)direct_children()
update generated documentation
Merge pull request #392 from gordon/docs

update generated documentation