Warn to stderr when "enhanced" console logging methods called without log level arg

[prometheas]

After the console object has been "enhanced", a warning message should be written to stderr every time that any of the logging methods (see below) are called without a first "log level" string argument.

// bad
console.log('a single string');
console.log('two', 'strings');
console.log('several stings also', 'warn', 'unless the first arg is a log level');

// good
console.log('info', 'some message');
console.warn('some message');
console.error('another', 'message');