Update getting started docs to use representation builder

[bruno]

The current getting started docs at
​http://kauriproject.org/docs-0_3/192-kauri/190-kauri.html

show how to create a template representation by depending on the template service. The more recommended approach would now be to use the representation builder, so the documentation should be adjusted. (the current example might still be valuable too, need to think about putting it somewhere else)

[mpo]

0.4 should do a documentation effort
if more elaborate ideas are floating around: please share.