Functional testing maybe shouldn't skip commits

[MichaelClerx]

At the moment functional testing does this:

1. Update to latest pints and pfunk
2. Run next test

Wondering if maybe we should insist each test is tried once with every commit? Would make it very slow though, possibly creating a backlog if pints commits are coming fast?

[MichaelClerx]

Actually it should! If we do every commit chronologically, we get intermingled branch stuff, like here: #784