Add additional config file options to CE using additionalProperty field

[alastair]

We have some fields in the tpl ini files that don't map to fields in the CE SoftwareApplication and ControlAction types (e.g. num_inputs, requires_docker, command_line, 'field' and 'encrypted' on Inputs.

It would be nice to semantically encode this information in the CE as well, so that anyone who comes along can understand the complete configuration for an algorithm just by reading the CE (without the need of the ini file too). We can do this by adding key-value fields to the additionalPropery field on nodes in the CE.