Implement 'kind' ClusterProvider

[In-Ko]

Description

Implementation of a ClusterProvider that can manage 'kind' clusters.

https://github.com/openmcp-project/cluster-provider-kind

It's a good idea to start with this one, because

1. kind does not require any kind of configuration, making this probably the easiest ClusterProvider implementation
2. it enables local development and testing

Prerequisite: #10

Open concern:

• cross cluster with kind, no networking experience yet

Leftovers after PoC

• Adapt to Cluster API
• Improve documentation in README
• Make repository open-source compliant
• Bring repository to github.com
• Add tests

Done Criteria

• Code has been reviewed by other team members
• Internal technical Documentation created/updated
• New / changed code is documented
• Unit Tests created for new code or existing Unit Tests updated
• Integration Test Suite updated (if applicable)
• Enduser Documentation updated (if applicable)
• Successful demonstration in Review

[In-Ko]

SInce some required done criteria are not yet completely met, and internal testing is ongoing, we should not regard this as "done", therefore putting it back on "Active Sprint"

[In-Ko]

@reshnm / @Diaphteiros : Do you guys know the current state ? Would you be enabled enough to provide docu / tests and whatever else is missing here ? Otherwise I guess this will be blocked until around mid of next week ...

[In-Ko]

Moved to "on hold" for now until @ValentinGerlach is back.

[ValentinGerlach]

PoC is done but there are some TODOs left before we can close this issue. I have added them to the issue description.