Add EditorConfig file to blueprints

As discussed in #1426, EditorConfig file is added to blueprints. I have set defaults for html, css, js and hbs files and they can be modified if needed. The default is 2 space indents for all of them. Please take a look.

cc @abuiles @treyhunner @ccoenen
I am strongly opposed to this. I would assume that the point of this layout was chosen to make customisation dead-simple.