add mark-failure stage
This adds a manual stage to all pipelines. Clicking the manual action will mark the input (baseline, patch, ...) as a kernel bug or false positive. When it's necessary to re-classify given pipeline (e.g. make it a kernel bug insteadof false positive), then it's sufficient to run the action again and wait for pipeline_stats to pick this up.
Signed-off-by: Jakub Racek jracek@redhat.com