targets, use Sequential elaboration policy when possible

          For openaadl/ocarina#106

          profile

          For openaadl/ocarina#113

        For issue #106

      compatibility with older GNAT

      for RTEMS 4.11 and above

      Wait_For_Incoming_Events

          while back ..

        For issue #4

        For issue #4

          SPARK2014 elaboration and tasking restrictions.

          For issue #4