Move Custom Resource Definitions into crds directory

[Transmitt0r]

Hey, I'm trying to create a helm chart that depends on tekton. I wan't to bundle some PipelineTasks in a helm chart to deploy them more easily.

Right now, all the custom resource definitions are in the templates directory. They should probably be moved into the crds directory (ref https://helm.sh/docs/chart_best_practices/custom_resource_definitions/). That way, tekton could be used as a dependency in a helm chart where e.g. tasks are templated.