Fix crash on shutdown

StopAllMacros was called before th->wait(), allowing Macro::Stop()
to run concurrently with the other threads still inside
CheckConditions. This caused races on _conditionCheckFuture (called
from both threads) and _helperThreads.

This could happen if conditions / actions were marked to run in parallel
to the main loop.

lib/macro/macro.cpp

@@ -1316,7 +1316,14 @@ bool RunMacros()
 	return true;
 }
 
-void StopAllMacros()
+void SignalStopAllMacros()
+{
+	for (const auto &m : GetAllMacros()) {
+		m->SignalStop();
+	}
+}
+
+void WaitForAllMacros()
 {
 	for (const auto &m : GetAllMacros()) {
 		m->Stop();