CMD changes for latest OpenShiftRunner

[alanbchristie]

The runner does not set the container CMD any more. Instead it populates the container with an execute script (in the squonk work directory) and expects the container to run this automatically. This is achieved by relying on CMD being set to ./execute and the WORKDIR being set to the location of the execute script.

Change the container to...

1. Provide a helpful (default) execute script in the home directory
2. Ensure WORKDIR is set to the execute script's directory
3. CMD is set to ./execute