Support Book Catalogs, easy to view thumbnails of frontpage of books and search fast

• to create/view/search 'Catalogs'
  • which contains the thumbnails of frontpage of Books as icon
  • search by title(folder name of volumes)
  • currently, archives are not supported.
• change words 'Database' -> 'Catalog'
• change QuickCatalog app to static lib
• hide updateButton/updateAllButton
• MainWindow can open CatalogWindow
• more details to see v0.6.0_pre,v0.6.0_pre2,v0.6.0_pre3,v0.6.0_pre4,v0.6.0_pre5