* Basic process metrics
* Enable Prometheus by an environment variable
* Code formatting
* Documentation for Prometheus metrics
* Link from README to documentation of Prometheus
* Link from README to documentation of Prometheus
* Link from README to documentation of Prometheus
* Separate module for metrics + tests
* Metrics limited by IP
* Metrics are forbidded for all requets by default
* Code refactoring
* allowedIps passed as a string to PrometheusMetrics
* Handle missing config
* METRICS_PROMETHEUS_ALLOWED_IPS added to documentation
* Log info about enabled metrics
* Unused code removed
* package-lock.json updated
* prom-client updated to 11.1.2
* Code refactoring
* Do not read IP address from X-Forwarder-For header
We use arrow functions in most places; this enforces it.
Passing arrow functions to Mocha is discouraged: https://mochajs.org/#arrow-functions
This was a mix of autofixes and hand adjustments.