support sass and css

[olets]

Use a "styles" or "stylesheets" folder, run less on src/styles/*.less, sass on ...*.scss, minify less/scss/css together.

Preserving cascade order is a potential problem, but for now safe to assume that no single project will mix less, scss, and css.

For Sass, see https://github.com/gulpjs/gulp/blob/master/docs/recipes/server-with-livereload-and-css-injection.md and (scroll down to "setting up tasks") https://community.nitrous.io/tutorials/setting-up-gulp-with-livereload-sass-and-other-tasks

[JoelSutherland]

It's easy enough to add Sass -- it can compile just like LESS. I'd like some help/direction on how to make it toggle-able with LESS. Nobody will use both so I don't want both to be a requirement but I don't yet know enough about Gulp to do this right.

[rickerd]

In my PR #16 i've added support for Sass and dropped LESS.
Since less is getting a bit old Sass is the new standard.

I hope you'll like it.