Remove the 'build_all' alias, now that 'stage' is built by default too.

[SVN r53815]

Jamroot

@@ -640,12 +640,6 @@ Use 'bjam install --prefix=<path>' if you wish to install headers and
 libraries to a different location and remove the source tree.\n\n"
   ;
 
-
-# Just build the libraries, don't install them anywhere. This is what happens
-# with just "bjam --v2".
-alias build_all : libs/$(libraries)/build ;
-
-
 # This rule should be called from libraries' Jamfiles and will create two
 # targets, "install" and "stage", that will install or stage that library. The
 # --prefix option is respected, but --with and --without options, naturally, are