code: public static Option editConfigurationFileExtend(String configurationFilePath, String key,
          Object value) {
          return new KarafDistributionConfigurationFileExtendOption(configurationFilePath, key, value);
      }
docs: This option allows to extend configurations in each configuration file based on the
  karaf.home location. The value extends the current value (e.g. a=b to a=a,b) instead of
  replacing it. If there is no current value it is added.
  <p>
  If you would like to have add or replace functionality please use the
  {@link KarafDistributionConfigurationFilePutOption} instead.
  
  @param configurationFilePath
  configuration file path
  @param key
  property key
  @param value
  property value
  @return option