code: function knFetchSchema(args, callback)
  {
  	var sources = args['sources'];
  	knValidateSources(sources);
  	knFetchMany(sources, {}, knFetchSchemaOne, function (err, schemas) {
  		if (err)
  			callback(err);
  		else
  			callback(null, knMergeSchemas(schemas));
  	});
  }
docs: /*
  Public entry point for fetching a bunch of schemas and returning the merged
  object.  Arguments include:
  
  sources		array of sources, as defined above for knMakeSource.
  Each source is usually obtained via knParseEnv or
  knMakeSource on a command-line option.