Add Prefix about loglevel

[mren]

Would be nice to have this on a per level basis.

log.setPrefix("info", "Info: ");
log.setPrefix("debug", "[MyPrefix]");
log.info("Hello World"); // Output "Info: Hello World"
log.debug("Hello World"); // Output "[MyPrefix]Hello World"

This would allow a more generic configuration.

[pimterry]

Sorry, I've been extraordinarily busy recently. Back on it now!

This is interesting, but doing things like this typically breaks stacktrace reporting from log messages. I'm currently trying to avoid letting this library expand too far beyond just providing a reliably hardy console alternative that works everywhere, so I don't want to implement this directly, but I can see how this would be useful.

Fortunately, I've just added a plugin API! See https://github.com/pimterry/loglevel#plugins for some explanation and an example.

I haven't yet released a new version including this, but it's in lib/loglevel.js on master, and if you wanted to give that a go and see if it solves your problem I'd be very keen to know how you got on. I'll be doing a proper release within the next few days or so, once I've done some more thorough testing.

If you want to bundle up a loglevel plugin for this and publish it yourselves I'd also be happy to link it from the README over here, in case anybody else is looking for the same sort of thing.

[iotaweb]

@pimterry The simplicity of logLevel and clever use of localStorage is a major appeal to me, so I like the fact you want to keep it lean, but with an API for those who wish to extend it.

I can see where the request comes from for context (and timestamp is nice too), but in exploring a lot of logging libraries lately, losing stacktrace reporting is a big deal (it makes $log in angular.js next to useless IMO).

So +1 for keeping it lean and thanks for sharing this library!