Update README.md

[MattPlayGamez]

Which category is this pull request?

• [ ] A new feature/enhancement.
• [ ] Fix an issue/feature-request.
• [ ] An improvement to existing modules.
• [x] Other (Please mention below).

Where has this been tested?

• Python Version
  • [x] v3.x
  • [x] v2.x
• Operating System:
  • [x] Linux (Please specify distro)
  • [x] Windows
  • [x] MacOS

Does this close any currently open issues?

No

Does this add any new dependency?

No

Does this add any new command line switch/argument?

No

Any other comments you would like to make?

I changed the README.md so people know how to install it with pipx. pipx is a command line utility that works like pip (ex. pipx install git+https://github.com/EnableSecurity/wafw00f.git) but makes a Virtual environment so dependencies do NOT interfere with each other and can be directly used without manually enabling the virtual environment. All automatically