Adds StatefulSet support (#549)

* Adds StatefulSet support

# Conflicts:
#	helm/opengist/templates/pvc.yaml

* Adds statefulset support for replicaCount gt 1

* Improves the setup of multiple replicas in a stateful set

* Adds config wrangling logic to the secret template

* Adds shared PV functionality

* Adds missing pvc-shared template

* Adds stateful set and documentation

---------

Co-authored-by: Guillem Riera <guillem@rieragalm.es>

helm/opengist/Chart.yaml

@@ -2,7 +2,7 @@ apiVersion: v2
 name: opengist
 description: Opengist Helm chart for Kubernetes
 type: application
-version: 0.4.0
+version: 0.5.0
 appVersion: 1.11.1
 home: https://opengist.io
 icon: https://raw.githubusercontent.com/thomiceli/opengist/master/public/img/opengist.svg