Duplicate algorithm implementations

[tatticoder]

I found 2 implementations for merge sort here and here.
Both are pretty similar in approach and solve same problem in same programming language.
One of them should be removed to reduce confusion and easier understanding.
I also suggest contributor should be notified for making a spam pull requests and Maintainers who merged requests without reviewing the code properly.

[sunilgknair051]

@tatticoder , thanks for the heads up. I think on a rainy day there would have been a situation wherein the maintainers never looked at the content of the commit before merging. Our bad, sorry!

@sukritishah15, please do have a look.

Thanks!