Added a broader amount of browser support

Now supports your default webbrowser instead of just Iceweasel, if you didn't have Iceweasel installed it would throw an exception when you run the script with the --open argument. Now it makes use of the [webbrowser](https://docs.python.org/2/library/webbrowser.html?highlight=webbrowser#webbrowser.open_new_tab) standard library.

I'm not quite sure but wouldn't it be a better idea to visit the created report files instead of the actual pages to view the information you just retrieved?

Also fixed some more path joining flaws which I've overlooked before.