Can you make FibonacciHeapNode.Data be settable?

[jmschuaquico]

I would like to avoid runtime memory allocations by creating a pool of FibonacciHeapNode. But that means being able to set the Data after the node's creation.

[sqeezy]

This would also be consistent with the remainder of the type.
Same here. Best to create a pull request. I promise to create a new nuget package as that's not automated yet.