2.2.2 - Filetree features and bugfixes

• new section "filetree" in configuration file;
• independent ajax calls for filetree and fileview #103, #104;
• selectable supports custom scrollbar (scrolling + selection);
• bugfix: missed custom scrollbar for preview mode;
• bugfix: bugfix: breadcrumbs is broken if "exclusiveFolder" is set #107;
• bugfix: close button issue on integration with CKEditor #108;