Add support for `.scss.erb`

[envygeeks]

Description

Rails supports .scss.erb, and other types of files aside from .js and the basic stuff that this Language currently provides. It would be nice if .css.erb, .scss.erb and a few others were added as it's quite common for us to use ERB for our SCSS to extract data at build time. Especially for static sites that use pieces of Rails (Sprockets) without Rails.