[contrib] Add DiffLlama-0.3B-handcut NeuronX port#75

dhwanw wants to merge 3 commits intomainaws-neuron/neuronx-distributed-inference:mainfrom

contrib/DiffLlama-0.3B-handcutaws-neuron/neuronx-distributed-inference:contrib/DiffLlama-0.3B-handcutCopy head branch name to clipboard