Include new Sass partials.

docs/css/s2-docs.scss

@@ -7,8 +7,10 @@
 @import "s2-docs-nav";
 @import "s2-docs-footer";
 @import "s2-docs-alert";
+@import "s2-docs-home";
 @import "anchorjs";
 @import "jumbotron";
+@import "prettify";
 
 .btn-toolbar {
   margin-bottom: 20px;