Merge pull request #588 from common-workflow-language/release

update MANIFEST so we can release a new version

Author: mr-c

MANIFEST.in

@@ -2,6 +2,7 @@ include gittaggers.py Makefile cwltool.py
 include tests/*
 include tests/tmp1/tmp2/tmp3/.gitkeep
 include tests/wf/*
+include tests/override/*
 include cwltool/schemas/v1.0/*.yml
 include cwltool/schemas/draft-2/*.yml
 include cwltool/schemas/draft-3/*.yml