Flo updates

Updated and reviewed following chapters:

• whole src/passwords

  • src/passwords/passwords-and-2fa/ has been split into: (1) src/passwords/passwords, (2) src/passwords/password-managers and (3) src/passwords/2fa

• whole src/files

  • src/files/destroy-sensitive-information has been split into (1) src/files/destroy-sensitive-information and (2) src/files/destroy-identifying-information

• src/phones-and-computers/malware

• src/phones-and-computers/physical-security

Also edited some misspelled words in other files.