rename loggregator_endpoint to metron_endpoint

[#74960322]
add metron package and job

[#74960322]

Signed-off-by: Joseph Rodriguez <jrodriguez@pivotallabs.com>
automatic promotion by GoCD workflow LoggregatorIntegrationTest/59 > IntegrationTests/1 > IntegrationTests

tests passed against https://github.com/cloudfoundry/cf-release/commit/9300fdfa1b45f36762211ae3a57279cf35fa72bf