Increase reliability of per patch perf job

CSIT-1485

- Measurement results are inconsistent, creating false positives.
- To avoid false positives, sensitivity has to be lowered.
+ Measurements are no more interleaved.
+ Measurement result are no longer filtered.
+ The job now runs faster.
- Ip6base regressions smaller than 4% are tolerated.
+ Ip6base false positives can happen, but less than 10% of the time.
- Part of job parameters is set on ci-management level.
+ Voter script output is improved.

Change-Id: I0ec7d5df8b397daf7ff0277a1137ee9f36d8d866
Signed-off-by: Vratko Polak <vrpolak@cisco.com>