🎉 (hopefully last) Release Candidate of v3.0.0

🆕 🆙 Changes since v3.0.0-rc.5 (skipped test release rc.6)

By far the largest breaking change for you as a k3d user is the change of the CLI syntax.

in k3d v1.x (and v3.0.0 up to rc.6), we used to have the VERB NOUN syntax, similar to how kubectl and kind have it
- e.g. k3d create -n mycluster (v1.x) or k3d create cluster mycluster (v3.0.0-rc.6)
NEW: Now we decided to follow the route of other major cloud CLIs (like gcloud, awscli, az, etc.) and roll with NOUN VERB syntax, which makes the CLI cleaner and easier to develop
- e.g. k3d cluster create, k3d kubeconfig get, ...
- Please checkout k3d help or the command tree on the website as a reference

To be as inclusive to the community as possible, we decided to get rid of all occurrences of master and worker in our code. Here is what changed:

master (node role) -> server (similar to k3s)
- e.g. k3d cluster create multi-server --servers 3
worker (node role) -> agent (similar to k3s)
- e.g. k3d cluster create multi-agent --agents 2
- Important: Due to this renaming, the short-hand flag k3d cluster create -a now stands for --agents and not anymore for --api-port (which does not have a short-hand flag anymore)
master (branch) -> main