Add osCheckODE() function so scripts can configure for running with legacy physics engine.

Function returns 'true' of the physics engine is configured to be 'OpenDynamicsEngine'.
  The presumption is that all other physics engines work the same (like SL) or it is a bug.
  Does not require ossl functions to be enabled.

OpenSim/Region/ScriptEngine/Shared/Api/Runtime/OSSL_Stub.cs

@@ -420,6 +420,11 @@ namespace OpenSim.Region.ScriptEngine.Shared.ScriptBase
             return m_OSSL_Functions.osGetScriptEngineName();
         }
 
+        public LSL_Integer osCheckODE()
+        {
+            return m_OSSL_Functions.osCheckODE();
+        }
+
         public string osGetPhysicsEngineType()
         {
             return m_OSSL_Functions.osGetPhysicsEngineType();