Make the analysis of experiments more flexible

• Allow arbitrary prometheus range queres (update prometheusResponse)
• Allow usage of more than one slo checker
• Update the json which send to the python slo checker
• refactoring
• Update CRDs in order to set the query string as an dedicated parameter for a slo checker
• Update exisiting python slo checker in order to use the new JSON format (handled in !185 (merged))

Closes #249 (closed)

helm/templates/theodolite/role-binding.yaml

 {{- if .Values.rbac.create -}}
-apiVersion: rbac.authorization.k8s.io/v1beta1
+apiVersion: rbac.authorization.k8s.io/v1
 kind: RoleBinding
 metadata:
   name:  {{ include "theodolite.fullname" . }}