Added an optional 'sorting' parameter to Tree.expand_tree() so that tree traversal can be operated without sorting nodes. Parameter defaults to True (sorting enabled) in order to keep backward compatibility.
Rationale: if children sorting is always enabled it's impossible to traverse the tree preserving the original insertion order or, better, it is necessary to explicitly keep track of insertion order using other attributes.
Added an optional 'sorting' parameter to Tree.expand_tree() so that tree traversal can be operated without sorting nodes. Parameter defaults to True (sorting enabled) in order to keep backward compatibility. Rationale: if children sorting is always enabled it's impossible to traverse the tree preserving the original insertion order or, better, it is necessary to explicitly keep track of insertion order using other attributes.