- Added rust requirements for cryptography.
- Removed installing requirements.txt as it's no longer needed.
- Added a call to `--download-plugins` to ensure plugins are bundled automatically.
Mainly worked on authorized_keys and pam persistence modules. Also added
the `load` command allowing users to load custom modules from different
directories. Lastly, added the optional inclusion of a
`$XDG_CONFIG_HOME/pwncat/pwncatrc` configuration allowing you to specify
configuration for all invocations of pwncat (like a custom module directory).
