Creation of girder job models via REST endpoints in worker plugin

[kotfic]

Deliverables:

• Post to endpoint that creates a girder job

Technical Notes:

• Parent-child is one to many
• How will we implement access control on creating jobs?
• How should access control be implemented for job creation?
• Depending on how restrictive we want to be this to be we may want require that jobs can only be created if they are children of existing jobs

Depends on:

• Allow parent-child relationships between girder job models ( Allow parent-child relationships between girder job models #2017 - see note above)

[zachmullen]

Re: access control, for the first pass we can require a special token scope that allows job creation, and create such a token just for the worker to use. Thus, ordinary users could not just create jobs arbitrarily.