Fix handling of functional test runner parameters --extended, --cutoff, and --startfrom
There are now three clearly separate configurations possible w.r.t. test runtime:
- Run tests below particular runtime (default, with 40 sec cutoff).
- Skip tests below particular runtime.
- Run all tests.
New tests are treated as 0 runtime and thus run both in default configuration and with --extended.
Fixes critical bug in !36 (merged) causing new (untimed) tests to never run.