Adding 'Headless' support.

[NullArray]

I think i will add some code that allows DorkNet to be run headless so without Geckodriver being in the way. In general when working, you do so from the terminal, at least with scripts such as these. Why not make it a little easier to multitask by having the option of not having Geckodriver's window in the way while running DorkNet.

[NullArray]

Added some code but the --nogui option apparently doesn't really work with the way in which the proxy is configured. If the user chooses to configure a proxy during the execution of DorkNet of course.

So for now i put the commit up but have left the relevant parts commented out, feel free to remove the comments and give it a shot. If you're not connecting through a proxy it should run in headless mode just fine.