Update templates with compatibility attributes

[zerospiel]

• added core CAPI contracts
• added providertemplates capi and crds versions
• added compatibility to the clustertemplates
• runtime: added support for multiproviders via multi-annotations to allow set provider crds contracts separately per provider only for clustertemplates

#543

Core CAPI ProviderTemplate chart:

annotations:
  cluster.x-k8s.io/v1beta1: ""
  cluster.x-k8s.io/v1alpha3: ""
  cluster.x-k8s.io/v1alpha4: ""

Example of a provider's ProviderTemplates supported CRDs contracts for a related CAPI version:

annotations:
  cluster.x-k8s.io/provider: infrastructure-aws
  cluster.x-k8s.io/v1alpha3: v1alpha3
  cluster.x-k8s.io/v1alpha4: v1alpha4
  cluster.x-k8s.io/v1beta1: v1beta1_v1beta2

Example of a ClusterTemplate contract per-provider requirements:

annotations:
  cluster.x-k8s.io/provider: infrastructure-aws, control-plane-k0smotron, bootstrap-k0smotron
  cluster.x-k8s.io/bootstrap-k0smotron: v1beta1
  cluster.x-k8s.io/control-plane-k0smotron: v1beta1
  cluster.x-k8s.io/infrastructure-aws: v1beta2

New status in a ClusterTemplate object:

status:
  # ... other values
  providerContracts:
    bootstrap-k0smotron: v1beta1
    control-plane-k0smotron: v1beta1
    infrastructure-aws: v1beta2
  providers: 
  - bootstrap-k0smotron
  - control-plane-k0smotron
  - infrastructure-aws