Render Note field hints consistently for "new" and "edit" forms

- The "Edit" form didn't have Markdown hints.
- The "New" form had a paperclip icon for attachments, the "edit" form
  didn't.

Closes #2010

Closes internal https://dev.gitlab.org/gitlab/gitlabhq/issues/2525

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

@@ -3,10 +3,7 @@
     = note_target_fields(note)
     = render layout: 'projects/md_preview', locals: { preview_class: 'note-text' } do
       = render 'projects/zen', f: f, attr: :note, classes: 'note_text js-note-text js-task-list-field'
-
-      .comment-hints.clearfix
-        .pull-left #{link_to 'Markdown ', help_page_path('markdown', 'markdown'),{ target: '_blank', tabindex: -1 }}
-        .pull-right #{link_to 'Attach a file', '#', class: 'markdown-selector', tabindex: -1 }
+      = render 'projects/notes/hints'
 
     .note-form-actions
       .buttons

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

@@ -8,18 +8,8 @@
   = f.hidden_field :noteable_type
 
   = render layout: 'projects/md_preview', locals: { preview_class: "note-text", referenced_users: true } do
-    = render 'projects/zen', f: f, attr: :note,
-      classes: 'note_text js-note-text'
-
-    .comment-hints.clearfix
-      .pull-left
-        = link_to "Markdown ", help_page_path("markdown", "markdown"),{ target: '_blank', tabindex: -1 }
-        tip:
-        = random_markdown_tip
-      .pull-right
-        = link_to '#', class: 'markdown-selector', tabindex: -1 do
-          Attach a file
-          = icon('paperclip')
+    = render 'projects/zen', f: f, attr: :note, classes: 'note_text js-note-text'
+    = render 'projects/notes/hints'
     .error-alert
 
   .note-form-actions

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

@@ -0,0 +1,9 @@
+.comment-hints.clearfix
+  .pull-left
+    = link_to 'Markdown', help_page_path('markdown', 'markdown'), target: '_blank', tabindex: -1
+    tip:
+    = random_markdown_tip
+  .pull-right
+    = link_to '#', class: 'markdown-selector', tabindex: -1 do
+      = icon('paperclip')
+      Attach a file