Adding a button to download in a .pdf file the generated password

[ErmannoOliveri]

Description

I added a button that using jsPDF can create a file called "password.pdf" with the generated password.

Motivation and Context

solve issue: #37

How Has This Been Tested?

I tested all the functioning of the functionalities and does not change in any way the functioning of the previous code

Screenshots:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.