Add ability to attach basic system info with report a issue dialog

I would like attach some basic info/possibly more detailed too (Option disabled by default) about the hardware while reporting issues which would help the developers solve the issues faster by giving them more info.
This should contain purely technical info with no user identifiable info about installed software or IP address.

**Edit: To add body to github, use https://github.com/elementary/switchboard-plug-about/issues/new/?body=hello**