Add support for other heuristics (e.g. Bastien & Scapin)

[edouard-lopez]

I'm not familiar with the Nielsen heuristic and reading your sidebar (which is a good idea) didn't help a lot (disclaimer: I didn't put a lot of energy into it :).
A famous heuristic as been described by D. Scapin & C. Bastien: Critères ergonomiques de Scapin et Bastien.

I'm aware it is possible to add custom ruleset, just want to have a place to centralised/share others heuristic for your extension.

[edouard-lopez]

Bastien & Scapin criteria in French and as a raw Google translation.