Fixed logic issue involving subdirectories during index creation.

In cases where the target ivfDir does not already exist, only some of the necessary subdirectories were being created, leading to exceptions on index creation.

src/main/java/gov/nih/nlm/nls/metamap/dfbuilder/CreateIndexes.java

@@ -220,6 +220,13 @@ static void prepareDirectories(String ivfdir)
       ivfDir.mkdir();
       tablesDir.mkdir();
       indicesDir.mkdir();
+
+      cuiconceptDir.mkdir();
+      cuisourceinfoDir.mkdir();
+      cuistDir.mkdir();
+      meshtcrelaxedDir.mkdir();
+      varsDir.mkdir();
+
     }
   }