The README does not document the default log level of the library

[alexanderkjeldaas]

For someone looking at software that uses this library, the primary question for a reviewer is: what does this software log?

To answer this, the README should state what the defaults are for this library.

The only place this is documented in the README is this sentence:

Note: By default log writes to os.Stderr Note: The default log level for log.Print is trace

This does not give information about about whether a log.Info(... will appear in stderr or not, or what the default behavior it.