TypeError: Cannot find function trim in object overqualified-elements.

When parsing my css files with `--format=lint-xml` i get following error in xml file:

```
-bash-4.1$ cat csslint.xml
<?xml version="1.0" encoding="utf-8"?><lint>
js: uncaught JavaScript runtime exception: TypeError: Cannot find function trim in object  overqualified-elements.

-bash-4.1$ csslint --version
v0.10.0
```
