Provide configuration support for nodeSelector, podAnnotations, and resources

[akirillov]

What would you like to be added:
The possibility to configure operator deployment parameters such as nodeSelector, podAnnotations, and resources.

Why is this needed:
Currently, there's no structured way to provide the requested configuration. While it is possible to develop a workaround for resources by explicitly exposing all the required fields - there's no way to provide either a key-value collection for podAnnotations and nodeSelectors or a complex parameter in a YAML format for such a property as podAffinity.

In Helm, this problem is solved by using values files and a custom toYaml templating function which allows specification of any of these parameters in a valid YAML syntax in the file.

Examples:

• nodeSelector
• podAnnotations

[kensipe]

Need for KEP which likely includes details for #988

[porridge]

Status update:

1. ability to create parameters of type map - is in v0.11.0. You can use this test operator as an example and there is a docs PR
2. ability to dump a parameter value as YAML inside a template - is also in v0.11.0 and documentation for it is in the canonical place now. Basically it's to be used identically like the function with the same name in Helm.
3. ability to conveniently pass complex parameter values into kubectl kudo - will be in the v0.12.0 release, its documentation will be merged right after the release. In v0.10.0 however you should be able to still pass them in JSON format (which is a subset of YAML) on the --parameter flag as explained in How could I use a struct as a parameter ? #951 (comment).

[porridge]

All three KEPs are now implemented and released or pending release, as explained in the status update above.