Squashed 'cwltool/schemas/' changes from ab086ad..c344fa4

c344fa4 Merge branch 'master' into draft-4
6c2a2bd Ported draft-2 schema to schema salad proper for validation by current cwltool.

git-subtree-dir: cwltool/schemas
git-subtree-split: c344fa4

Author: Peter Amstutz