Handle the hardcoded configuration values

This patch allows to customize the hardcoded configuration values,
as well as introduce new configuration options for ceilometer services
by configmap template with the specified section:

  ceilometer:
    server:
      configmap:
        DEFAULT:
          rate_limit_interval: 0
          rate_limit_burst: 0
          rate_limit_except_level: CRITICAL
        coordination:
          max_retry_interval: 30
    agent:
      configmap:
        DEFAULT:
          rate_limit_interval: 0
          rate_limit_burst: 0
          rate_limit_except_level: CRITICAL
        coordination:
          max_retry_interval: 30

Change-Id: Ifec9bdf7756fd8e77cd960a13b9176aa6f00d268
Related-Prod: PROD-29627
13 files changed