Unbreak install

[SVN r52365]

Jamroot

@@ -602,8 +602,6 @@ class top-level-target : alias-target-class
     
 }
 
-alias install : install-proper install-unversioned ;
-
 targets.create-metatarget top-level-target : [ project.current ]
   : install
   : install-proper install-unversioned