heroku/heroku-buildpack-php — pull request #77 by aheusser (2014-08-15 18:31:45+00:00)
Title: Look at NEW_RELIC_CONFIG_FILE for user-provided agent configuration

As is the convention for the python agent (see https://docs.newrelic.com/docs/agents/python-agent/hosting-services/python-agent-and-heroku#agent-configuration-file) ... we rely upon NEW_RELIC_CONFIG_FILE to allow the user to supply any additional agent configuration.