feat(pcf): Add possibility to read QoS values from file

Changes

• Add possibility to add QoSData to the policies
• Add new config option to specify QoSData filesystem path
• Implements #11 (closed)

Tests / How to use

• You have to create a new folder in the policies, e.g. openair-pcf/policies/qos_data:
• You create a file (name does not matter)
• Add you QoS rules, e.g.:

internet-qos-nongbr:
  5qi: 9
  maxbrUl: 100 Mbps
  maxbrDl: 200 Mbps
  arp:
    priorityLevel: 15
    preemptCap: NOT_PREEMPT
    preemptVuln: PREEMPTABLE
  priorityLevel: 10

internet-qos-gbr:
  5qi: 5
  maxbrUl: 100 Mbps
  maxbrDl: 200 Mbps
  gbrUl: 50 Mbps
  gbrDl: 50 Mbps
  arp:
    priorityLevel: 1
    preemptCap: MAY_PREEMPT
    preemptVuln: NOT_PREEMPTABLE
  priorityLevel: 10

And then you add these rules to one of your PCC rules, e.g.:

internet-rule:
  flowInfos:
    - flowDescription: permit out ip from any to assigned
  precedence: 10
  refTcData:
    - internet-scenario
  refQosData:
    - internet-qos-nongbr