Instrument our sample apps for Jaeger

Once we launch Jaeger, we should instrument our sample apps. This would server two prime use cases:

1. Provide a simple demo app that can be used both internally and externally to try out the functionality, much like we have for sample AutoDevOps apps.
2. Provide customers with a simple instrumented app which they can look at, to get an idea of how easy it is to instrument their own.

First priority would be the AutoDevOps samples: https://gitlab.com/auto-devops-examples We could also the GitLab CI example projects: https://gitlab.com/auto-devops-examples