Added More Command Examples for New Users in nettacker.py

[ARYAN03B]

Fixes #740

Checklist

• [x] I have followed the Contributor Guidelines.
• [ ] The code has been thoroughly tested in my local development environment with flake8 and pylint.
• [x] The code is Python 3 compatible.
• [x] The code follows the PEP8 styling guidelines with 4 spaces indentation.
• [x] This Pull Request relates to only one issue or only one feature
• [x] I have referenced the corresponding issue number in my commit message
• [x] I have added the relevant documentation.
• [x] My branch is up-to-date with the Upstream master branch.

Changes proposed in this pull request

In your Python code (nettacker.py), consider adding more command examples. This helps new users who may find it difficult to create the right commands when they use your code for the first time. It makes it easier for them to write the correct code.

Like that:-

nettacker -L en -v -o results.txt -i target.com -m ftp_brute,ssh_brute -u admin -P passwords.txt -g 21,22 --start-api --api-host 0.0.0.0 --api-port 5000

[securestep9]

There is a major code refactoring ongoing right now with additional work done as part of Google Summer of Code 2024. We will include your suggestions once the new version of Nettacker with refactored codebase is released at the end of August