The `Modules/hashlib.h` helper file is now removed and split into multiple files:
* `Modules/_hashlib/hashlib_buffer.[ch]` -- Utilities for getting a buffer view and handling buffer inputs.
* `Modules/_hashlib/hashlib_fetch.h` -- Utilities used when fetching a message digest from a digest-like identifier.
Currently, this file only contains common error messages as the fetching API is not yet implemented.
* `Modules/_hashlib/hashlib_mutex.h` -- Utilities for managing the lock on cryptographic hash objects.
OpenSSL and HACL*-based hash functions constructors now support both `data` and `string` parameters.
Previously these constructor functions inconsistently supported sometimes `data` and sometimes `string`,
while the documentation expected `data` to be given in all cases.
This matches the GIL releasing behavior of our existing `_hashopenssl`
module, extending it to the HACL* built-ins.
Includes adding comments to better describe the ENTER/LEAVE macros
purpose and explain the lock strategy in both existing and new code.
This changes the main documentation, doc strings, source code comments, and a
couple error messages in the test suite. In some cases the word was removed
or edited some other way to fix the grammar.
