Moved from WordCraft's crates/docx/src/crypt.rs (07f97737): agile and
standard decryption, agile encryption, the ISO and legacy protection
password hashes. The compound file is read and written with craft-cfb
and the descriptor parsed with craft-xml.
From GridCraft's crates/xlsx/src/crypto.rs (5cf52c5f): check(), named
unsupported schemes, rights-managed files, the password key encryptor
chosen by its URI, and independent key vectors.
