std.xml should just go

[Walter Bright]

Max Samukha wrote:
> .NET and Qt do have slices of some kind:
> 
> http://msdn.microsoft.com/en-us/library/1hsbd92d.aspx
> http://doc.qt.nokia.com/latest/qstringref.html#details
> 
> I am not sure whether their XML libraries use those.

.net's slices are inadequate, because its strings are not interchangeable with 
slices. When they're not interchangeable, then you wind up being forced to make 
copies.