[blocked]Add filter interface to any filterable resource view

Currently, the only way to add filters to resource view is when they're inside a `ckanext-dashboard`. Ideally, we could add these filters anywhere a filterable resource view is displayed.
@vitorbaptista I guess the avoiding of numeric fields has to do with pulling a large number of options for continuous fields. But it is also a limitation that you can't filter by fields which are eg years or numeric codes (like *date* and *to_id* in this example).

If I understood correctly we are making a distinct query with a limit of 20 when populating the filter dropdown, so perhaps we could also include the numeric fields? Or it is because of the way queries are constructed in the datastore backend?

![untitled](https://cloud.githubusercontent.com/assets/200230/3675270/c55afad8-127d-11e4-9dfd-d0d24f6e0a3c.png)