Add enhanced influxdb-relay queries logging

[toni-moreno]

I would like control who is querying my databases and how many resources it is spending.

A good library to this component would be

https://github.com/rs/zerolog

https://github.com/rs/zerolog#integration-with-nethttp

I propose log the following fields

For all query endpoints (/prom,/write/,/query/,etc)

• Client IP
• User
• URI (/query, /write/ etc)
• influx database
• measurement/s ( should explore body in /write and query in /query)
• retention policy
• amount of data sent
• response time
• precision

Specific for /query

• Range Time queried. ( from to)
• influx server sent
• referer
• grafana_refresh_time ( when grafana querys small refresh time could crash the database, this info is locate inside the referer)