Add helper for simplifying Bugzilla file uploads

[cvan]

It would be really slick if you could drag and drop an image or paste a URL to an image (or Cloud/Dropbox/imgur page) and that would turn it into a real Bugzilla file upload. That way it would be preserved forever.

[robhudson]

:+1:

[gkoberger]

Thanks for volunteering! ;)

[rik]

@cvan Could you open a bug for Bugzilla directly? I'm pretty sure this is a feature the Bugzilla team would be happy to add.

[rik]

In the mean time, it would be nice to add support for this in this extension.

[regrev]

The one feature I get the most complaints about is the clunkyness of the file upload process. Basecamp has this feature implemented right, but Basecamp is not as nearly as powerful as Bugzilla in many (most) respects. Drag+drop files in Bugzilla would be awesome!