Add todo spec test for libsass issue 254

sass/libsass#254

Author: mgreter

spec/libsass-todo-issues/issue_254/expected_output.css

@@ -0,0 +1,5 @@
+body {
+  border-color: "#ccc"; }
+  @media only screen and (max-width: 900px) and (min-width: 400px) {
+    body {
+      border-color: black; } }

spec/libsass-todo-issues/issue_254/input.scss

@@ -0,0 +1,17 @@
+@mixin simple-media-query($max-width, $min-width) {
+      @media only screen and (max-width: $max-width) and (min-width: $min-width) {
+        @content;
+      }
+}
+
+@mixin test($value) {
+    border-color: $value;
+}
+
+body 
+{
+    @include test("#ccc");
+    @include simple-media-query(900px, 400px) {
+        border-color: black;
+    }
+}