TCT: added option order-trees for the comparison step for the AthenaMT tests
This MR adds the option --order-trees
for the comparison step in the AthenaMT TCT tests - as suggested by @elmsheus and @emoyse . Additionally there are few other updates:
- increased number of events for test q220
- updated the test recentrun_main_2018 to use AthenaMT with 8 threads (originally it was serial)
Tagging @rmazini