allow gridworks to load extensions also from the same place where data is stored (in the 'extension' subfolder')

git-svn-id: http://google-refine.googlecode.com/svn/trunk@1258 7d457c2a-affb-35e4-300a-418c747d4874

server/src/com/google/gridworks/Gridworks.java

@@ -239,6 +239,7 @@ class GridworksServer extends Server {
         ServletHolder servlet = context.getServletHandler().getServlet("gridworks");
         if (servlet != null) {
             servlet.setInitParameter("gridworks.data", getDataDir());
+            servlet.setInitParameter("butterfly.modules.path", getDataDir() + "/extensions");
             servlet.setInitOrder(1);
             servlet.doStart();
         }