(merge from head) Set the version number of msvc when configuring a default autodetected version.

[SVN r37657]

src/tools/msvc.jam

@@ -176,6 +176,7 @@ local rule configure-really (
         # take the first detected version
         version = [ $(.versions).all ] ;
         version = $(version[1]) ;
+        v = $(version) ;
 
         # Note: 'version' can still be empty at this point if no versions were 
         # detected.