BF: Let DAGMan submit files have a final newline
RF: Replace convoluted logic with template and keyword expansion
RF: Rename and uniformize option handling (backward-compatible)
NF: Wrapper command for DAGMan jobs

This enables checkpoint/migration wrapper to be combined for Nipype
workflows.
BF: Forgot to put the 'queue' command back in
NF: Option to block until DAGMan has finished

This will make it easier to use DAGMan-based workflows in other script
that do further processing of the output.
DOC: More useful docs
Merge pull request #626 from hanke/master

Update to DAGMan plugin