Update bindings to use newest OpenAPI Python Client library

[JakubFrejlach]

Currently osidb-bindings are frozen on the 0.10.7 version of OpenAPI Python Client library due to a usage of custom jinja templates. These templates and the whole templating API of the OpenAPI Python Client library is in the beta stage and it is unstable and thus updating the version (currently the newest version is 0.15.0) without any changes would break the bindings in a numerous ways.

Task here is to prepare all the necessary templates for the update to the newer version (eg. inject our custom exposed data, make templates more permissive to not require all the fields, etc.) and then proceed with the update.

As far as I know nothing extra useful was introduced in the newer versions so this issue should have very low priority for now.