Fix ignored fetcher timeout attribute for bug #30 of rdflib

This has been tested successfully with the following code, both with and without JQuery

```
<!DOCTYPE html>
<html>
<head>
    <title></title>
    <script src="rdflib.js"></script>
    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.8.1/jquery.min.js"></script>

</head>
<body>


<script>
    function createNewRdfStore() {
        var store = new $rdf.IndexedFormula();
        var fetcherTimeout = 10000;
        $rdf.fetcher(store, fetcherTimeout, true);
        return store;
    }
    var store = createNewRdfStore();


    var urlToFetch = "http://bblfish.net/people/henry/card";
    var urlToFetchTimeout = "http://purl.org/captsolo/semweb/foaf-captsolo.rdf";
    var urlToFetchTimeout2 = "http://unknown.localhost.com";
    var urlToFetchTimeout3 = "https://localhost:8443/srv/cors?url=http://purl.org/captsolo/semweb/foaf-captsolo.rdf";

    store.fetcher.nowOrWhenFetched(urlToFetchTimeout3, undefined, function(isError,errorStatus) {
        console.error("isError?",isError," Status=",errorStatus)
    });

</script>
</body>
</html>
```

In my case I needed a cors proxy to be able to simulate the timeout because there were errors due to same origin policy.
Btw these errors were not very explicit in errorStatus :(