Incorrect property syntax in README.md

[MarkJamesHoward]

In the Declarative Rendering section of README.md it seems to be using lit-html syntax rather than how we use properties in LitElement where we'd need to specify the 'this' keyword?

So rather than:

attribute: html<div class="${color} special"></div>

we should have

attribute: html<div class="${**this**.color} special"></div>

[MarkJamesHoward]

Added a PR for the same #198

[MarkJamesHoward]

Checking #196 and I'm not sure if this is correct now, if we no longer need to reference 'this' then the getting started code example in README.md will need to have 'this' removed from the whales property?
That said I've created a plain project with 0.6.0 and it complains if I don't provide 'this' within the render method.