Allow building of shared versions of some Boost.Test libraries.

Adjust tests to use always use static linking to Boost.Test, since
linking to the shared version requires test changes.

Patch from Juergen Hunold.


[SVN r35989]

test/Jamfile.v2

@@ -2,7 +2,7 @@
 rule sc-test ( name : extra-sources * )
 {
     return [ 
-      run $(name).cpp /boost/test//boost_unit_test_framework $(extra-sources) ]
+      run $(name).cpp /boost/test//boost_unit_test_framework/<link>static $(extra-sources) ]
     ;
 }