[Feature Request] Nmap importer

Hello,

During assessments, I prefer to handle all the scans manually because I know what kind of parameters I want (or do not want).

It would be nice to be able to import nmap scans already made to enrich a sketch instead of scanning again a target or manually add ports. Naabu can also export a scan with nmap's XML format, enhancing its integration with flowsint.

Thank you