Update dsls.md (#49)
Update dsls.md (#49)

* Update dsls.md

The example did not work out of the box.
This are the alterations i needed to make it work with v1.0

* Update dsls.md

* Update dsls.md

And i needed to implement the methods for dslengine.Root

goadesign-jp/goa.design,goadesign-jp/goa.design,goadesign-jp/goa.design,goadesign/goa.design,goadesign/goa.design,goadesign/goa.design