Display file size instead of mode in tree/blob partial

app/views/tree/_blob.html.haml

@@ -3,7 +3,7 @@
     %i.icon-file
     %span.file_name
       = blob.name.force_encoding('utf-8')
-      %small #{blob.mode}
+      %small= number_to_human_size blob.size
     %span.options= render "tree/blob_actions"
   - if blob.text?
     = render "tree/blob/text", blob: blob