Support run xline as a etcd

[liangyuanpeng]

What would you like to be added?

xline is a kv storage and wrote with rust, compatible with etcd's API, also is a CNCF project.

And this issue is request kwok can support xline as a component.

/assign
/cc @Ming

Why is this needed?

It is convenient for people to try running xline with kwok, also can add a adopters for kwok.

[liangyuanpeng]

/cc @wzshiming

[wzshiming]

I plan to define a component configuration for kwokctl, and should be able to add/remove/replace components. this will be added to the list of things to consider.
#847

[liangyuanpeng]

Awesome! seems like it will also working for components such as prometheus and jaeger.

[wzshiming]

Yes, the expectation is general enough.