Unit Tests - bug.489.t

- The command line construct "tags.none:" is translated into the expression
  "tags = ''", but instead of '=' I had entered '=='.  Force of C/C++/Perl
  habit.

src/A3.cpp

@@ -937,7 +937,7 @@ const A3 A3::expand (const A3& input) const
       else if (mod == "none")
       {
         expanded.push_back (Arg (name, "dom"));
-        expanded.push_back (Arg ("==", "op"));
+        expanded.push_back (Arg ("=",  "op"));
         expanded.push_back (Arg ("",   "string"));
       }