Add implementation for /generator (aka /generate) path

[magicmatatjahu]

We have merged first draft of the OpenAPI document for our Server API. We should implement first path and create first structure of the source code:

• create controller for /generator (aka /generate) path
• create needed services (for generator and also for archiver)
• create middlewares to validate request body (based on given operation from OpenAPI document), template's parameters, sent AsyncAPI document
• handle errors
• write tests

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[BOLT04]

Hi @magicmatatjahu, PR #7 solves this issue right?

[magicmatatjahu]

@BOLT04 Yeah, it solves :)

[magicmatatjahu]

Implemented by #7