Reposition voiced rests (Issue 3902) (issue 101720045)

[PhilEHolmes]

Reviewers: ,

Message:
Please review

Description:
This moves voiced rests closer together, more closely matching the
recommendations of Gould, Read, etc.  There are a lot of regression test
changes, but all associated with repositioned rests.

Please review this at https://codereview.appspot.com/101720045/

Affected files (+1, -1 lines):
  M lily/rest.cc


Index: lily/rest.cc
diff --git a/lily/rest.cc b/lily/rest.cc
index  
2dbb2c9f9b3d465d135f65a376fce240cb709c36..f8746ce4d2ec29e5a8ed4eb18ba52f6d65659317  
100644
--- a/lily/rest.cc
+++ b/lily/rest.cc
@@ -72,7 +72,7 @@ Rest::staff_position_internal (Grob *me, int  
duration_log, int dir)
       return pos;
     }

-  pos = 4 * dir;
+  pos = 2 * dir;

   if (duration_log > 1)
     /* Only half notes or longer want alignment with staff lines */