Fixes #6897: Print styles get own .less file

less/bootstrap.less

@@ -1,7 +1,7 @@
 /*!
  * Bootstrap v3.0.0
  *
- * Copyright 2012 Twitter, Inc
+ * Copyright 2013 Twitter, Inc
  * Licensed under the Apache License v2.0
  * http://www.apache.org/licenses/LICENSE-2.0
  *
@@ -9,11 +9,12 @@
  */
 
 // Core variables and mixins
-@import "variables.less"; // Modify this for custom colors, font-sizes, etc
+@import "variables.less";
 @import "mixins.less";
 
 // Reset
 @import "normalize.less";
+@import "print.less";
 
 // Core CSS
 @import "scaffolding.less";