Api principles (preliminary, very rough draft)

@mezis understood. I think it would be nice to have an alternative to Rails.

@amencarini My concern is that DSL's are usually sugar for object instantiation (instead of using MyClass.new) and as such its hard to unit test because the DSL creates the objects you want to test and there is usually no way to get a copy of those objects, therefore you have to do a higher level test (such `Rack::Test`). I might be overthinking things... but my question would be how do we test non-HTTP response things, e.g. that a KissMetrics event is fired.