This package includes:

* github.com/prometheus/common/log: wraps https://github.com/sirupsen/logrus
in order to add line:file annotations to log lines, as well as to provide
common command-line flags for prometheus components using it.
* github.com/prometheus/common/model: shared data structures
* github.com/prometheus/common/expfmt: decoding and encoding for the
exposition format
* github.com/prometheus/common/route: a routing wrapper around
https://github.com/julienschmidt/httprouter using `context.context`
* github.com/prometheus/common/client_model: data model artifacts for
prometheus (compiled protobuf).