Simplify handling of <library-file> feature.

* common.jam (resolve-library-files): Remove
* msvc.jam, cw.jam: Add 'flags' invocation for library-file feature.


[SVN r31918]

tools/build

@@ -1 +1 @@
-Subproject commit 13d6eaa4dd88a42778a40a6d0c6786d95eff5e38
+Subproject commit e8b3e6c725b9cb66b1e0e2b7b733963cc27d1194