Add conditions to the KubeadmControlPlane object

[fabriziopandini]

User Story As a developer/user/operator I would like to have conditions documenting the operational state of KubeadmControlPlane objects

Detailed Description A KubeadmControlPlane controls a set of machines that compose the cluster control plane.

I'm proposing to start implementing the following conditions for the KubeadmControlPlane object:

• MachinesReady, reporting the aggregation of the Ready conditions from the machines controlled by the KubeadmControlPlane object
• CertificatesGenerated
• UpgradeSucceeded
• ResizeSucceeded
• Initialized

Anything else you would like to add: As required by the condition CAEP, the KubeadmControlPlane objects should also provide a Ready condition describing the overall state of the object.

Being the control plane a key component in the cluster most probably we are going to add more conditions over time; so you should consider this as the first iteration on KubeadmControlPlane conditions. Also, after the first set of the condition is merged on a core set of object, we should audit the result and refine

/kind feature

[vincepri]

/milestone v0.3.7

[fabriziopandini]

/assign /lifecycle active