Convert existing namespace into kintohub environment

[bakayolo]

Is your feature request related to a problem? Please describe.

As a user, I want to import an existing namespace into KintoHub so that I can manage it in KintoHub.

Describe the solution you'd like

Make sure to have a popup asking the user they understand the consequences of doing that.

• We have restrictions on the name of all the resources created
• We don't support all configurations so you might end up overriding some configuration
• We only manage a subset of resources (deployment, service, ingress, etc)