Makes sure that everything is imported in tests

lib/src/store/numeric_encoder.rs

@@ -703,10 +703,11 @@ impl<S: StringStore + Default> Default for Encoder<S> {
 }
 
 mod test {
-    #[test]
-    fn test_encoding() {
     use model::*;
+    use store::numeric_encoder::*;
 
+    #[test]
+    fn test_encoding() {
         let encoder: Encoder<MemoryStringStore> = Encoder::default();
         let terms: Vec<Term> = vec![
             NamedNode::from_str("http://foo.com").unwrap().into(),