Merge branch 'emper-test-runner' into 'master'

emper/Actor.hpp

emper/Runtime.cpp

emper/Runtime.hpp

tests/AlarmFutureTest.cpp

tests/CancelFutureTest.cpp

tests/IncrementalCompletionTest.cpp

tests/LinkFutureTest.cpp

tests/ReuseBpsTest.cpp

tests/ReuseFutureTest.cpp

tests/TellActorFromAnywhereTest.cpp

tests/TimeoutWrapperTest.cpp

tests/TooLongFutureChain.cpp

tests/YieldToAnywhereTest.cpp

tests/test-runner/test-runner.cpp

tests/test-runner/test-runner.hpp