Provide command for configuring extension libraries

[garethbowen]

Is your feature request related to a problem? Please describe. Allowing app devs to provide libraries which can be invoked from configuration is being added to cht-core. At the moment the only way to configure this is directly uploading docs to couchdb which is unnecessarily complex and error prone.

Describe the solution you'd like Add a command to make this simple.

Describe alternatives you've considered

• Solid documentation: still hard to use, no help for automation.
• App Management change: doesn't help automation, not best practice.

[garethbowen]

Merged.