Abstract Wikipedia team/Observability/Logging

All of our log events can be seen on our main Wikifunctions LogStash board

Defining Log Severity Level:

Name	Level	Usage
'trace'	10	for active debugging
'debug'	20	detailed logs in cases where we want to do follow-up on issues
'info'	30	normal events, e.g. 'incoming request'
'warn'	40	potentially worrying events
'error'	50	worrying events where we can't return a useful response
'fatal'	60	for environmental issues, e.g. 'port cannot be opened'

This is in accordance to the bunyan logging library we are currently using.