Initialise receiver/elasticapmreceiver

[axw]

Create a skeleton for the elasticapm receiver, for receiving data from Elastic APM/RUM agents.

[AlexanderWert]

cc @rogercoll

[rogercoll]

(some CI checks failing, should be fixed by running make license-update)

Skeleton looks great to me. I think it would be interesting to start with the following in a follow-up PR:

• Translators: move the APM Event to Otel pdata translations to a custom package. Similar to https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/pkg/translator/opencensus
  • Do you know if there is any repository/source where we can get json modelpb.Batch examples for unit testing?
• README.md with support matrix
• testdata: Integration test with the expected generated signals

[lahsivjar]

LGTM!

[lahsivjar]

@axw Also, looks like the mdatagen used to generate the code is old. You may need to update that in you local. OTOH, I think there is something wrong with the tools setup of mdatagen in the repository... it seems to use the global one.

[axw]

@axw Also, looks like the mdatagen used to generate the code is old. You may need to update that in you local. OTOH, I think there is something wrong with the tools setup of mdatagen in the repository... it seems to use the global one.

Indeed, I've pushed a fix to Makefile.Common to add the tools dir to $PATH