v0.4.1

Release v0.4.1

Bug Fixes:
- Differentiate prompt syntax for standard bash, zsh and sh (#126)
- Added `-c=never` to `ip` command in `linux.enumerate.system.network`
  (#126)
- Updated Dockerfile to properly build post-v0.4.0 releases (#125)
- Added check for `nologin` shell to stop pwncat from accidentally
  closing the session (#116)
- Resolved all flake8 errors (#123)
- Improved EOF handling for Linux file-writes (#117)