Handle missing files/URLs gracefully.

If no version of a URL is found the importer just skips the URL now instead of throwing an error.

lib/deb_importer.rb

@@ -39,7 +39,11 @@ module DebImporter
     def i18n(component, language)
       url = "#{@dist_url}/#{component}/i18n/Translation-en"
       file = find_and_open_compressed_url(url)
-      return get_paragraphs(file)
+      if file
+        return get_paragraphs(file)
+      else
+        return []
+      end
     end
 
     # Look for the file or URL in various compressed formats
@@ -68,9 +72,12 @@ module DebImporter
 
           return file
         rescue Errno::ENOENT
-          Rails.logger.error "URL #{url} could not be opened. Skipping."
+          Rails.logger.debug "URL #{url} could not be opened. Skipping."
         end
       end
+
+      Rails.logger.error "No file found at #{url} and various compression extensions."
+      return nil
     end
 
     # Try to load the Packages file for a certain component (e.g. "main")