Memory used from single algorithm

[Helias]

Add a function/parameter to see the memory used for each single algorithm tested

[nishihatapalmer]

I would also like to see this. Some algorithms use a lot more memory than others.
It is also interesting to benchmark algorithms that are using the same amount of memory.
Quite a few algorithms would support tuning their memory usage (e.g. ones that use hash-based lookup tables), to provide a better comparison between them.

[nishihatapalmer]

I'm currently working on a PR to gather stats from running algorithms. memory usage is one of those stats.