* Support for using <tag> renaming in any target.

* Added some fake targets for the specific files in a stage.
* features.jam, added <tag> feature, as always relevant.


[SVN r15752]

tools/build

@@ -1 +1 @@
-Subproject commit 454c979d49bcf1dd3ae866d7c9afbf6b2f16541c
+Subproject commit 45ee2552867a864a8a22363c1e6b43fe8919fc94