shouldIgnoreOutput() fails when snapshots change / Review output filtering

[seanpoulter]

This issue is a folllow-up on this suggested code change in #215. @marcinczenko pointed out that shouldIgnoreOutput() fails when the snapshots change.

This is a placeholder to discuss what the filtered output should look like, and suggest changes.

cc @marcinczenko

Expected

TBD: ??

Actual

TBD: ??