Improved library manager:

- Manage files of books and documents in the app: you can copy, move, rename, delete a duplicate file, quickly go to a book or document file in the "About document" section.

- Ability to exclude folders, individual books, and documents from scanning.

- Folders got a counter of supported books and documents.

Added Telugu and Gujarati interface languages. Thanks to Vijesh Varma and Kamlesh Bhankharia for the translation.