Generate client for API service

[uniqueg]

Is your feature request related to a problem? Please describe.
In order to easily allow a Python service to make use of the TEStribute API service (#25), a client should be auto-generated based on the OpenAPI specs.

Describe the solution you'd like
Bravado can be used for auto-generating the client to a large extent, as is done in, e.g., TES-cli. The client should be available in a separate repository TEStribute-cli within the elixir-europe organization.

Describe alternatives you've considered
N/A

Additional context
N/A

[uniqueg]

Maybe let's see first how we deal with the generic Bravado client. I feel that this may not really be necessary then.