Lost the 'bool' in 'bool double' in Numerics.AreEqual (#12)

src/framework/Constraints/Numerics.cs

@@ -100,7 +100,7 @@ namespace NUnit.Framework.Constraints
         /// <returns>True if the values are equal</returns>
         public static bool AreEqual(object expected, object actual, ref Tolerance tolerance)
         {
-            _double = (expected is double || actual is double);
+            bool _double = (expected is double || actual is double);
             if (!_double && (IntPtr.Size == 8))
                 _double = (expected.GetType () == nfloatType || actual.GetType () == nfloatType);