Setting improve update

@bbauer @ceckert
the previous pull request related to this was so fast becuase the query was returning  0 results ... woops. 
Querying on Setting.where(value: 'foo') would always return an empty array because value is serialized on the model. This stores the data in the db in a funny format. I decided to go with filtering by the name including widget_id.

Wrote a spec around this, went red then green. So we should be good now.

Damn serialized attrs...