Merge branch 'revert_note_caching' into 'master'

revert caching of note text

This MR reverts the caching of note texts because what is rendered as a link in Markdown depends on the user's access to other projects and groups.

Until we find a solution that doesn't decrease security, let's not use the cache for this.

See discussion in gitlab-org/gitlab-ce!911 for more information.

/cc @DouweM @stanhu @vsizov

See merge request !1014

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

@@ -56,7 +56,6 @@
 
 
       .note-body{class: note_editable?(note) ? 'js-task-list-container' : ''}
-        = cache [note, 'markdown', user_color_scheme_class] do
         .note-text
           = preserve do
             = markdown(note.note, {no_header_anchors: true})