Consider adding additional API operations

[uniqueg]

It may be useful to add a few additional, non-standard API operations, such as:

• POST /service-info to set the service info
• DELETE /tasks/{id} to completely delete a task run and all associated objects (created files etc.)

Perhaps there are others?

Have a look at other apps like TRS-Filer and DRS-Filer for inspiration for additional operations and how these can be specified and used in FOCA.