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
@ccoenen your argument makes sense to me.  I wanted to bring it up in case section grouping wasn't known.

I always use the same indentation for my HTML, CSS, JS, and HBS.  Changing 4 lines is easier for users than adding new sections.