Support for multiple applications

[dkrizic]

I would like to be able to configure multiple applications like this

service:
  applications:
    - name: yasm-frontend
      namespace: frontend
      storageType: configmap # or in memory
      configMap:
        name: yasm-frontend
        preset: BANNER=Hello
        editable: BANNER
      workload: # for restarting a workload
        enabled: true
        type: deployment # Type of the workload
        name: yasm-frontend # Type of the workload
    - name: yasm-backend
      namespace: backend
      storageType: configmap
      configMap:
        name: yasm-backend
        preset: AUTH_ENABLED=true,BACKGROUND=blue
        editable: BACKGROUND

So basically the same functionality, but with the difference, that multiple applications can be configured. The CLI should have the name -a or --application flag and be able to receive the list of applications, like

feature-cli applicaitons
feature-cli -a yasm-frontend getable
feature-cli -a yasm-backend set BANNER "Hello, World"

There should be also an argument called --default-application or DEFAULT_APPLICATION, that is used if no application is specified.

The RBAC needs allow operations on multiple namespaces.