Fix for issue #41.  Each to a MakeVariable method resulted in a new tosca::context being constructed because the tosca::context argument was being passed by value.  Corrected the signature in CppMethodMakeVariable to pass the context by reference.
Fix for issue #41.  Each to a MakeVariable method resulted in a new tosca::context being constructed because the tosca::context argument was being passed by value.  Corrected the signature in CppMethodMakeVariable to pass the context by reference.

TransScript/TransScript,crsx/crsx4,tosca-lang/tosca,tosca-lang/tosca,tosca-lang/tosca,TransScript/TransScript,crsx/crsx4