Add support for Change Control Scheduling

[ksArista]

go-cvprac is currently missing support for change control scheduling, as well as other convenience methods around the ChangeControlConfig endpoint.

Equivalent code for scheduling can be found here for the python CVPrac bindings.

This slightly violates go-cvprac v3's version compatibility of "2020.1.x, 2020.2.x": the endpoint specifies a min version of "CVP 2021.2.0 or newer" , while scheduling requires CVP 2022.1.0.

[burnyd]

This wouldnt be too difficult to implement given this pr that was done a while ago. This is leveraging the inventory resource APIs so it should follow similar ideaology. I am not exactly sure how this would also work with the semantic versioning of this project.

Do you want to do a PR assembling the same sort of logic as the above? I planned on doing something similar because it is or will be required for the CVP terraform plugin.

[ksArista]

@burnyd Thanks for the pointers -- I was planning to pick this up myself shortly. I've filed an issue to (primarily) document the versioning weirdness.