Fixed bug in css2sass that caused whitespace indentation issues for c…

…omma-delimited rules in the original CSS.

lib/sass/css.rb

@@ -237,7 +237,7 @@ def expand_commas(root)
       root.children.map! do |child|
         next child unless Tree::RuleNode === child && child.rule.include?(',')
         child.rule.split(',').map do |rule|
-          node = Tree::RuleNode.new(rule, nil)
+          node = Tree::RuleNode.new(rule.strip, nil)
           node.children = child.children
           node
         end