djvubind: Add docstrings
djvubind: Add docstrings

DIYBookScanner/spreads,DIYBookScanner/spreads,gareth8118/spreads,gareth8118/spreads,DIYBookScanner/spreads,adongy/spreads,miloh/spreads,miloh/spreads,gareth8118/spreads,miloh/spreads,nafraf/spreads,nafraf/spreads,nafraf/spreads,adongy/spreads,adongy/spreads