What would you like to be added:
Colorize numeric log levels with levelColor or similar, or at least allow the log to be printed anyway.
E.g. {"level": 30, "msg": "A message"}

Why is this needed:
Some log libraries use numeric log levels instead of the, in my experience, more usual debug, info, warn etc. When using the template function levelColor on numeric values it throws an error.

expanding template failed: template: log:1:70: executing "log" at <$d.level>: wrong type for value; expected string; got json.Number

It would be nice if levelColor could colorize numbers too, or at least allow the log line to be printed anyway.