Updates READEME instructions for use in addons
Updates READEME instructions for use in addons

I seriously just wasted 4 hours debugging this, had to read the source code to see how these were supposed to be setup. 
This dir structure was not obvious to me as I am used to seeing the addon styles int he `addon/app` dir. 

Please accept this change to save people (and me when I will inevitably forget how it should be done) time.
webark/ember-component-css,ebryn/ember-component-css,webark/ember-component-css,ebryn/ember-component-css