Extra-measures for tabs closed by scripts

Immediately stop loading the Webview : might solve issues with some videos continuing playing after tab close.
Better handling of the Web Inspector provided by WebKit in Unified layout

If we only have the Web Inspector in our menu, then let ArticleList’s menu prevail
Note/reminder :
To enable the Web Inspector, type in Terminal :
	defaults write uk.co.opencommunity.vienna2 WebKitDeveloperExtras -bool true
To disable it, type in Terminal :
	defaults delete uk.co.opencommunity.vienna2 WebKitDeveloperExtras
Better handling of file://localhost/ like URLs
Always stop loading the Webview when the tab closes
Merge pull request #314 from barijaona/bugfixes

Various bugfixes