Apply ability filter user containers from among others

[AndrienkoAleksandr]

Description

In the Che 7 Workspace Model, a user is able to define a list of own "containers" and apply Che Plugins "tooling containers". Then all containers(machines) are available in Workspace#getRuntime#getMachines but it is not possible to identify which of containers are user-defined.
It makes sense to have an ability to identify where container comes from User Recipe or Che Plugin since this list is used for opening a terminal, executing of command.
A special attribute in Machine#getAttributes would be fine.

[garagatyi]

Well, sometimes it makes sense to execute command or have a terminal into tolling containers too! For example into Theia container

[sleshchenko]

Well, sometimes it makes sense to execute command or have a terminal into tolling containers too! For example into Theia container

@garagatyi Yeah, I agree. Let me clarify that Client would be able not just filter machines, but like order them (like first user-defined and then tooling) or display some labels near machine names to make it clear where it comes from.

[skabashnyuk]

@evidolob @AndrienkoAleksandr I think I clarified my concerns with @l0rd. Maven/Git would not be a Che plugin as a separate sidecar. This issue has the correct and right description. You can proceed. Please don't forget that in multiuser Che jwt-proxy can be added and it's not a Che plugin and it's not defined in user recipe.

[slemeur]

What is your proposal for jwt-proxy then?

[skabashnyuk]

What is your proposal for jwt-proxy then?

Identify jwt-proxy in the same way as we identify Che Plugins as something that comes not from user recipe.

[AndrienkoAleksandr]

@skabashnyuk @evidolob @garagatyi @l0rd I created pull request #12386 to begin disscussion how to resolve this issue in best way.

[AndrienkoAleksandr]

Need for eclipse-che/che-theia#21 too