Configure issues raised by UUID version

[jkmartindale]

Thanks for making this extension! I've found it very useful, though a bit noisy for most of my engagements. I think users would benefit from being able to configure which UUID versions raise issues to whatever level makes sense for their assessments.

I have working code in my fork https://github.com/jkmartindale/burp-uuid that adds this configuration to the extensions context menu (and persists across Burp sessions via saveExtensionSetting()), though I figured before making a pull request I should ask if this is something you'd like upstream and what should be the default configuration.