uploader fixes

app/uploaders/beispieldatei_uploader.rb

@@ -12,6 +12,10 @@ class BeispieldateiUploader < CarrierWave::Uploader::Base
 
   # Override the directory where uploaded files will be stored.
   # This is a sensible default for uploaders that are meant to be mounted:
+def root
+  Rails.root.join 'public/'
+end
+
   def store_dir
     "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
   end