Parametrized benchmarks

[alexfmpe]

Can we somehow pass parameters to the frameworks? Say, through query strings.
Otherwise it's going to be a pain every time some hardcoded value needs to change, like with #310 & #312.

[krausest]

Sorry - I'm not going to do that. Would have helped with the swap change, but doesn't help for other changes like new benchmarks. I don't want to the added complexity for that.