test: update test-run

* Added "fragile" option with a list of tests that are not intended to
  be run in parallel with others. The format of the list is the same as
  for "disabled" option (#187, PR #188).
* Ensured that non-parallel test suites and fragile tests will be run
  only when all parallel ones will be finished (PR #188).
* Fixed reporting in case of lack of temporary result (PR #172).