Don't accept multiple sources for 'compile' tests,

and it's broken anyway.
If we cannot determine the library name, return path,
to make the test rules minimally useful outside Boost.


[SVN r36622]

tools/build

@@ -1 +1 @@
-Subproject commit edcb4b1f707ba1e2259e28139626a5735e7e1637
+Subproject commit 34d70b1e677c6dc79ef2df50c8de91cb8b6e0323