c# tree traversal: fixed index out of range issue

[henrikac]

This PR fixes an issue in the DFSRecursiveInorderBinary method where

if (tree._children.Count > 0)
{
    DFSRecursiveInorderBinary(tree._children[0]);
    Console.WriteLine(tree.Id);
    DFSRecursiveInorderBinary(tree._children[1]);
}

would throw an IndexOutOfRange exception if tree._children.Count == 1.

This PR also removes a couple of redundant this. in the constructors.

Note: The first line in Tree.cs says "// submitted by Julian Schacher (jspp)" and I am not sure if I should make any changes to this line or add something like "modified by ..." because this is not the exact code submitted by Julian?

[leios]

Yeah, we kinda changed things since tree traversal was added and are really inconsistent with the "submitted by" notes. I think either removing the note or adding a "modified by..." would both be ok solutions to the note

[henrikac]

I removed the submitted line to make it more consistent with the examples in other languages.

[Amaras]

@lazyprop That basically is resolving the merge.

[leios]

I think this is a straightforward change and am happy to merge it. The line numbers seem fine.

I'll wait a second to see if anyone who knows more C# has anything to say before merging. If anyone else wants to click the button, feel free!

[Amaras]

Looks good to me as well (I don't know C Sharp that well, but it's readable enough)