Added scheduling parameters to helm template; (#249)

Issue #, if available:
Closes [#1038](aws-controllers-k8s/community#1038)

Description of changes:
This adds affinity, toleration and priorityClassName to the deployment spec as optional parameters.
They default to none, so this will not change any existing functionality.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Author: philnichol

templates/helm/templates/deployment.yaml

@@ -75,3 +75,12 @@ spec:
           value: {{ join "," .Values.resourceTags | quote }}
       terminationGracePeriodSeconds: 10
       nodeSelector: {{ toYaml .Values.deployment.nodeSelector | nindent 8 }}
+      {{ if .Values.deployment.tolerations -}}
+      tolerations: {{ toYaml .Values.deployment.tolerations | nindent 8 }}
+      {{ end -}}
+      {{ if .Values.deployment.affinity -}}
+      affinity: {{ toYaml .Values.deployment.affinity | nindent 8 }}
+      {{ end -}}
+      {{ if .Values.deployment.priorityClassName -}}
+      priorityClassName: {{ .Values.deployment.priorityClassName -}}
+      {{ end -}}

templates/helm/values.yaml.tpl

@@ -15,9 +15,20 @@ deployment:
   annotations: {}
   labels: {}
   containerPort: 8080
+  # Which nodeSelector to set?
+  # See: https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#nodeselector
   nodeSelector:
     kubernetes.io/os: linux
-
+  # Which tolerations to set?
+  # See: https://kubernetes.io/docs/concepts/scheduling-eviction/taint-and-toleration/
+  tolerations: {}
+  # What affinity to set?
+  # See: https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#affinity-and-anti-affinity
+  affinity: {}
+  # Which priorityClassName to set?
+  # See: https://kubernetes.io/docs/concepts/scheduling-eviction/pod-priority-preemption/#pod-priority
+  priorityClassName:
+  
 metrics:
   service:
     # Set to true to automatically create a Kubernetes Service resource for the