[UUI] Chart changes for uui-server 15.0.2

[UUI] Chart changes for uui-server 15.0.2

- define tracing properties in global section to allow centrally
  configuring it (for the whole platform)
- define uui-server properties in values.yaml
- use MaxRAMPercentage jvm arg to scale the jvm heap size
  dynamically with the pod resources (and give the process
  more than 128MB(!) max heap)
- add a revisionHistoryLimit setting
- do not use NodePorts
- change default service type for nginx to ClusterIP

Issue-ID: USECASEUI-875
Change-Id: I3c7893f4970c088844511ea5b038bf842ce90859
Signed-off-by: Fiete Ostkamp <Fiete.Ostkamp@telekom.de>