FEATURE: User page refactor

Re-organise user page so it is easier to find interesting info
split it into tabs

- Introduce notifications and messages tabs
- Stop couting stuff for the user page to speed up rendering
- Suppress more information when viewing your own profile

app/serializers/user_serializer.rb

@@ -70,7 +70,7 @@ class UserSerializer < BasicUserSerializer
              :automatically_unpin_topics
 
   has_one :invited_by, embed: :object, serializer: BasicUserSerializer
-  has_many :custom_groups, embed: :object, serializer: BasicGroupSerializer
+  has_many :groups, embed: :object, serializer: BasicGroupSerializer
   has_many :featured_user_badges, embed: :ids, serializer: UserBadgeSerializer, root: :user_badges
   has_one  :card_badge, embed: :object, serializer: BadgeSerializer
 
@@ -118,6 +118,14 @@ class UserSerializer < BasicUserSerializer
   ### ATTRIBUTES
   ###
 
+  def groups
+    if scope.is_admin? || object.id == scope.user.try(:id)
+      object.groups
+    else
+      object.groups.where(visible: true)
+    end
+  end
+
   def include_email?
     object.id && object.id == scope.user.try(:id)
   end