[Sass] [SCSS] Add an overarching lib/sass/scss.rb file.

lib/sass/engine.rb

@@ -16,7 +16,7 @@ require 'sass/tree/debug_node'
 require 'sass/tree/import_node'
 require 'sass/environment'
 require 'sass/script'
-require 'sass/scss/parser'
+require 'sass/scss'
 require 'sass/error'
 require 'sass/files'
 require 'haml/shared'

lib/sass/scss.rb

@@ -0,0 +1,13 @@
+require 'sass/scss/rx'
+require 'sass/scss/script_parser'
+require 'sass/scss/parser'
+
+module Sass
+  # SCSS is the CSS syntax for Sass.
+  # It parses into the same syntax tree as Sass,
+  # and generates the same sort of output CSS.
+  #
+  # This module contains code for the parsing of SCSS.
+  # The evaluation is handled by the broader {Sass} module.
+  module SCSS; end
+end

lib/sass/scss/parser.rb

@@ -1,6 +1,3 @@
-require 'sass/scss/rx'
-require 'sass/scss/script_parser'
-
 require 'strscan'
 require 'set'