Fix usage

XmlSchemaClassGenerator.Console/Program.cs

@@ -67,8 +67,8 @@ static void Main(string[] args)
 A file name may be given by appending a pipe sign (|) followed by a file name (like schema.xsd) to the XML namespace.
 If no mapping is found for an XML namespace, a name is generated automatically (may fail).", v => namespaces.Add(v) },
  { "nf|namespaceFile=", @"file containing mapppings from XML namespaces to C# namespaces
-The format is one mapping per line, whitespace separated, XML namespace, C# namespace, and optionally file name.
-Lines starting with # are ignored.", v => namespaceFiles.Add(v) },
+The line format is one mapping per line: XML namespace = C# namespace [optional file name].
+Lines starting with # and empty lines are ignored.", v => namespaceFiles.Add(v) },
  { "o|output=", "the {FOLDER} to write the resulting .cs files to", v => outputFolder = v },
  { "i|integer=", @"map xs:integer and derived types to {TYPE} instead of automatic approximation
 {TYPE} can be i[nt], l[ong], or d[ecimal]", v => {