Improving Documentation on Advanced / Core Seldon Components

[axsaucedo]

Currently Seldon has documentation covering most interfaces but there are several components that could be documented further. This issue is the parent issue to several documentation issues that are currently in place including:

• Adding documentation covering inference graph and components Enhance Inference Graph Documentation #2011
• Documentation on Seldon Core Operator Is there any documentation that explains Seldon-core operator design & implementation? #1630
• Documentation on Seldon Core Microservice Add / Extend docs on seldon-core-microservice #2202
• Documentation on InitContainer Add documentation that dives into the iniContainer #2055
• Documentation on overriding current prepackaged servers to updated versions of the libraries Add documentation on how to extend base prepackaged servers with new images (xgboost, sklearn, etc) #2060

Other things to explore:

• Documentation on initContainer (and extending it to create own initContainer)

[ukclivecox]

We have updated docs now for V1 APIs. Can address in general for V2 APIs.