[#12] surefire-reporter: create dummy successful report when no exceptions found

 * when there were no exceptions reported, no actual jUnit XML report files
   were created. This caused problems on Jenkins, which would fail the build
   as it was expecting to found some report files.
Merge pull request #35 from psiroky/12-surefire-dummy-report

[#12] surefire-reporter: create dummy successful report when no exceptions found