Ability to list all resources in a given namespace

[jinnovation]

Currently, kele-list functionality is somewhat limited -- one group-version-kind + namespace combo, and that's it.

Let's add functionality analogous to kubectl get all that lists all of the resources in a given namespace.

With this, we can add a resource-specific suffix to kele-resource for namespaces e.g. [l]ist all resources.

Definition of Done

• Function implemented to list all resources in a given namespace using the kele-list interface
• Resource-specific suffix added to kele-resource allowing users to list all resources belonging to a specific namespace

[jinnovation]

Note that we've introduced kind-specific columns in #146 etc. When listing all resources, let's ignore kind-specific columns and only show the 'default' fields, e.g. name, namespace, etc.

[jinnovation]

Idea: bind s-k l to "list all resources in current context + namespace"

[jinnovation]

Implementation plan:

• Add in a custom variable kele-all-kinds that specifies which kinds that the user would like to
  fetch when fetching "all" resources in a namespace. Default value can be: Pods, Deployments,
  Services, and ConfigMaps.
• Add a new interactive command (defun kele-list-all (namespace) ...) that uses the kele-list
  interface to list all resources in that namespace
  • This should have an additional column to show the kind of the resource