Merge Sort using Linked List

[amanvatss]

Merge Sort using Linked Lists

Merge Sort is particularly well-suited for linked lists, leveraging their non-contiguous structure for efficient sorting. The process involves:

1. Divide and Conquer: The list is recursively split into smaller halves until each sublist contains a single node, simplifying the sorting process.

2.Merging: Sorted sublists are then merged in O(n) time, requiring no additional memory, unlike array-based sorting.

3.Stability: The algorithm preserves the relative order of equal elements, ensuring a stable sort.

Fixes #261