unify web.handlers

Unify URL import

URLSpec should take care of model importation not handlers settings in Application which let app import less.
say:
```python
handlers = [(r'/', 'Indexhandler')]
```
it works currently, however, 
```python
handlers = [url('/', 'Indexhandler', name='index')]
```
not working, it's not just wired but inconsistent. 

After patched both method works fine.