adding permutations to interface

src/pg/sql/16_getis.sql

@@ -6,10 +6,11 @@ CREATE OR REPLACE FUNCTION
       column_name TEXT,
       w_type TEXT DEFAULT 'knn',
       num_ngbrs INT DEFAULT 5,
+      permutations INT DEFAULT 99,
       geom_col TEXT DEFAULT 'the_geom',
       id_col TEXT DEFAULT 'cartodb_id')
-RETURNS TABLE (z_val NUMERIC, p_val NUMERIC, rowid BIGINT)
+RETURNS TABLE (z_val NUMERIC, p_val NUMERIC, p_z_sim NUMERIC, rowid BIGINT)
 AS $$
   from crankshaft.clustering import getis_ord
-  return getis_ord(subquery, column_name, w_type, num_ngbrs, geom_col, id_col)
+  return getis_ord(subquery, column_name, w_type, num_ngbrs, permutations, geom_col, id_col)
 $$ LANGUAGE plpythonu;