FR: list existing connection groups and connections and fill quick-access-menu

[jochenwezel]

Requirements

• remove/clear/hide quick-access menu when user is logged out
• when user is logged in, fill quick-access menu with available connections for currently logged in user
  • initially after login
  • clear menu cache from time to time (e.g. after 5 min) if menu is not active or quick access menu is opening

ToDos

• query connections + connection groups + put everything into parent/child hierarchy
• show/hide + clear/fill based on login status
• clear + show + create quick access menu incl. sub menu entries

[jochenwezel]

RestApiClient already supports (in a first version) querying connections+connection groups