Fix file upload for edit note. Better style for discussion form

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/stylesheets/sections/notes.scss

@@ -257,7 +257,8 @@ ul.notes {
 .file,
 .discussion {
   .new_note {
-    margin: 8px 5px 8px 0;
+    margin: 0;
+    border: none;
   }
 }
 .new_note {

app/views/projects/notes/_note.html.haml

@@ -34,7 +34,7 @@
         = markdown(note.note)
 
     .note-edit-form
-      = form_for note, url: project_note_path(@project, note), method: :put, remote: true do |f|
+      = form_for note, url: project_note_path(@project, note), method: :put, remote: true, authenticity_token: true do |f|
         = f.text_area :note, class: 'note_text js-note-text js-gfm-input turn-on'
 
         .form-actions