0.4.0 (May 29, 2019) -- run-baby-run

The minimum required DataLad version is now 0.11.5.

New features

- The call format gained the "{img_dspath}" placeholder, which expands
  to the relative path of the dataset that contains the image.  This
  is useful for pointing to a wrapper script that is bundled in the
  same subdataset as a container.

- `containers-run` now passes the container image to `run` via its
  `extra_inputs` argument so that a run command's "{inputs}" field is
  restricted to inputs that the caller explicitly specified.

- During execution, `containers-run` now sets the environment variable
  `DATALAD_CONTAINER_NAME` to the name of the container.

Fixes

- `containers-run` mishandled paths when called from a subdirectory.

- `containers-run` didn't provide an informative error message when
  `cmdexec` contained an unknown placeholder.

- `containers-add` ignores the `--update` flag when the container
  doesn't yet exist, but it confusingly still used the word "update"
  in the commit message.