refactor values meta data

Hi Marc,

I refactored the values meta data proposed by you to be more consistent with the rest of the app.

Other changes:
* isolated stuff that needs a JS runtime, `uglifier` is still needed in production but you can develop without it - see updated readme
* switched value and value2 for Winterthur, it makes more sense for me that way but let me know your thoughts

Please review and merge this to your master, thereby your [pull request](https://github.com/tpreusse/open-budget/pull/6) will be updated automatically and I can merge it to my master.

Thomas