fix winbuild link

jbmohler · jbmohler · commit 194af41a1bf0 · 2014-09-12T08:32:26.000-04:00
diff --git a/INSTALL b/INSTALL
@@ -319,4 +319,4 @@ Framework with Visual Studio).  In addition to Visual Studio `CMake
 
 Since there is no canonical Windows package manager the build methods for
 freetype, zlib, libpng, tcl, & tk source code are documented as a build script
-at `matplotlib-winbuild <https://github.com/jbmohler/matplotlib-winbuild>`.
+at `matplotlib-winbuild <https://github.com/jbmohler/matplotlib-winbuild>`_.
