Network Simulator API

[KonradBkd]

Subject

Experimental NetSim API candidate.

Description

Public API for user-implemented network simulator participants.

Instructions for review / testing

Review Code, Docs, Demos.

Developer checklist (address before review)

• [ ] Changelog.md updated (TODO!)
• [ ] Prepared update for depending repositories
• [ ] Documentation updated (public API changes only)
• [ ] API docstrings updated (public API changes only)
• [ ] Rebase → commit history clean
• [ ] Squash and merge → proper PR title

[KonradBkd]

Review Part 1 of N

@VDanielEdwards: Done