[RLlib; docs] Docs do-over (new API stack): Remove Catalog pages.

[sven1977]

Docs do-over (new API stack): Remove Catalog pages.

• To reduce the number of classes a user is exposed to when developing with RLlib, the Catalog API will be deprecated soon and replaced by simpler utility functions.

Why are these changes needed?

Related issue number

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[simonsays1980]

LGTM. I just wonder how users should use the RLModules when the Catalog is not replaced, yet, without these guides?

[sven1977]

LGTM. I just wonder how users should use the RLModules when the Catalog is not replaced, yet, without these guides?

Great question. 👍 👍 I would like to convert all the catalog magic that's in these classes right now into algo-independent utility functions that can be used by any RLModule, regardless of the algorithm used. Similar to the RLModule APIs.
We need to still do this work (carve out the code) and then document it properly .