Basic Charts view

closes #9 
I believe vectors or lighter weight, so instead of merging the hashes let's create nested vectors and then use (into)[http://clojuredocs.org/clojure_core/clojure.core/into]:

```clojure
(into {} (for [data-item data]
              [((keyword field_xpath) data-item)
               (:count data-item)]))
```