Makes it possible to use an installed docutils without referring to a

source distro directory.

[SVN r52306]

tools/build

@@ -1 +1 @@
-Subproject commit b15d1b6464e5b4a397c0c1e3c958fdf9639b73aa
+Subproject commit 7543e32ec9acf40d2ea7d38feebc2872403eba2a