External Cluster Management should automatically connect a cluster to ArgoCD

[cre8minus1]

Arlon recently added support to manage an external cluster, however users need to first add the cluster to argoCD. To make it easy for users who don't have argoCD running, or much experience with argoCD we should enhance the external cluster management to register the cluster to argoCD such that the following UX is achievable:

1. User downloads Arlon
2. User uses bootstrap to add ArgoCD, Arlon and ClusterAPI to their management cluster
3. User runs set workspace to configure their git repo where the active Profiles and ClusterSpecs will live
4. User runs `cluster connect' specifying an existing cluster, the cluster is added to ArgoCD and Arlon
5. User runs bundle and profile create, creating the profile and bundle objects
6. User runs cluster deploy specifying the profile and the profile is applied to an existing cluster

Aha! Link: https://pf9.aha.io/features/ARLON-142