* mps/code/trace.c (TraceRankForAccess): While in the ephemeron band,
use RankFINAL for final segments and RankEXACT for the others.
* mps/test/function/eph5.c: New Test.
* mps/test/testsets/passing: Include eph5.c.
* mps/test/test/testlib/ephfmt.h (union header): Use a one-word header.
* mps/test/test/testlib/ephfmt.c: Update accordingly.
* mps/test/function/eph1.c: Update accordingly.
