After aborting a thread, wait for it to actually finish. EXPERIMENTAL for OSG

testing. DO NOT UPDATE TO THIS UNLESS YOU KNOW WHAT YOU'RE DOING!

OpenSim/Region/ScriptEngine/Shared/Instance/ScriptInstance.cs

@@ -536,6 +536,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
             if (!m_InSelfDelete)
                 result.Abort();
 
+            result.Wait(TimeSpan.FromSeconds(10));
             lock (m_EventQueue)
             {
                 m_CurrentResult = null;