GUI: Sort headers in the Sampler result

[asfimport]

Marc Stern (Bug 66143): When using the GUI, we often have a lot of headers in the "Request headers" pane, and especially in the "Response header" one. Having a "Sort/Raw" option (button/checkbox/dropdown) allowing to alphabetically sort them (or not obviously) would, in some situations, be a great time saver. As this would be an option, it would stay backward-compatible. I hope someone could find the time to implement this. Thanks

OS: All