Add a changelog

[hroncok]

We should add a changelog (to REDAME?). It should say what changes since the fork from CPython and link to CPython 3.12.3 changelog for previous changes.

[encukou]

• This library exposes the crypt_r(3) function, not crypt(3).

  • crypt_r is not part of any standard. This library is tested with the crypt_r implementation in Fedora (libxcrypt, as of 2024), and should work with compatible implementations of crypt_r (such as libcrypt.so from older glibc).
  • Note that the improvements in crypt_r over crypt are in memory management and thread safety, not security/cryptography.

• It is easy to use crypt_r in an insecure way. Notably:

  • All hashing methods except METHOD_CRYPT (the original Unix algorithm from the 1970s) are optional platform-specific extenstions.
  • This library does not expose modern hashing methods like libxcrypt's yescrypt. The last wrapper update is from 2017.

[hroncok]

Thanks @encukou. I'll make sure to put that into the README as well.

[hroncok]

I opened https://github.com/fedora-python/crypt_r/pull/9 to add the changes mentioned here and to create the changelog section.

I plan to bump the version and add a specific changelog entry for it, once we are ready to release.