Merge pull request sass#100 from jhawthorn/avoid_searching_dirs

Avoid searching for files in nonexistant dirs

lib/sassc/rails/importer.rb

@@ -102,6 +102,9 @@ def imports(path, parent_path)
           search_paths.map! do |path|
             File.join(path, specified_dir)
           end
+          search_paths.select! do |path|
+            File.directory?(path)
+          end
         end
 
         search_paths.each do |search_path|