def with_context(context, start_at = nil, end_at = nil)
      Enumerator.new do |yielder|
        @stats.each do |stat|
          yielder << [stat[:name], resolve(stat[:name], context, start_at, end_at)]
        end
      end
    end
def with_context(context, start_at = nil, end_at = nil)
      Enumerator.new do |yielder|
        @stats.each do |stat|
          yielder << [stat[:name], resolve(stat[:name], context, start_at, end_at)]
        end
      end
    end
Public: Resolves every stat with the given context and return an enumerator

 context - An arbritrary context object to compute the result.
 start_at - A date to filter resources created after it
 end_at - A date to filter resources created before it

 Returns an Enumerator where each value is a tuple of name and resolved value