Update creds/http_form description

Adapt creds/http_form_* modules to Cisco Docsis

string.letters to string.ascii_letters

Store authorship information under the right key, "authors".

Exit by pressing Ctrl+D

Add 'cd routersploit' to installation instructions

Update password list with Adobe Top 100 leaked

- Add navigation to folder with repo
- Replace `apt` package manager with `pip` which is much universal(also used pip to install from `requirements.txt`

Make it work in Python 3