Collections : Supporting extending existing QueryMetadata

Here is a simple test case which demonstrates this possibility :

    @Test
    public void Reusage(){
        QueryMetadata metadata = new DefaultQueryMetadata();
        metadata.addJoin(JoinType.DEFAULT, cat);
        metadata.addWhere(cat.name.startsWith("A"));

        ColQuery query = new ColQueryImpl(metadata);
        query.bind(cat, cats);
        assertEquals(Arrays.asList(c3), query.list(cat));
    }

The new ColQuery.bind method supports this.