Merge tag '0.2.1' into develop

release/0.2.1 0.2.1
Added extra_command_formats to 'program' definition.
Now raises ProgramExistsError
Updated /media/ahayes/data/workspace/supervisor-confator/VERSION and /media/ahayes/data/workspace/supervisor-confator/CHANGELOG.md
Merge branch 'release/0.3.0'