Enhance GPU Hash Table with Dual-Key Support

[Abhijeetkumar96]

This update extends the existing GPU hash table implementation to support dual keys, enabling the storage and retrieval of pairs with two keys and their respective values. This enhancement significantly increases the data structure's flexibility and applicability in scenarios requiring complex key relationships.

Technical Improvements: - Dual-Key Support: Expanded the hash table's ability to store pairs with two keys, facilitating complex & sophisticated data-structures like graph edges. - 64-bit MurmurHash2 Algorithm: Adapted the MurmurHash2 hashing algorithm to efficiently manage and resolve dual-key entries. - CUDA_CHECKER Utility: Implements checks for CUDA operations like memory allocation and data transfer, enhancing error handling and debugging.