Added Profile tooltip

For consistency sake, the profile in the navbar has a tooltip.

app/views/layouts/_head_panel.html.haml

@@ -42,7 +42,7 @@
             = link_to destroy_user_session_path, class: "logout", method: :delete, title: "Logout", class: 'has_bottom_tooltip', 'data-original-title' => 'Logout'  do
               %i.fa.fa-sign-out
           %li.hidden-xs
-            = link_to current_user, class: "profile-pic", id: 'profile-pic' do
+            = link_to current_user, class: "profile-pic has_bottom_tooltip", id: 'profile-pic', 'data-original-title' => 'Your profile' do
               = image_tag avatar_icon(current_user.email, 60), alt: 'User activity'
 
 = render 'shared/outdated_browser'