Add support for encrypting Cisco Type 9 password

[alextremblay]

Environment

• netutils version: 1.3.0

Proposed Functionality

I would like to add an encrypt_type9 function to netutils.password, with a similar signature to the existing encrypt_type7 function.

Use Case

This would allow users to generate valid cisco type 9 password hashes to be embedded in their configs or compared against existing hashes in existing configs.

[itdependsnetworks]

Going to consolidate and manage here: #96