adding pgsql tests

src/pg/test/sql/16_getis_test.sql

@@ -0,0 +1,13 @@
+\pset format unaligned
+\set ECHO all
+\i test/fixtures/getis_data.sql
+
+-- set random seed
+SELECT cdb_crankshaft._cdb_random_seeds(1234);
+
+-- test against PySAL example dataset
+SELECT z_score, p_val
+FROM cdb_crankshaft.CDB_GetisOrdsG(
+  'select * from ppoints2',
+  'ratio') As cdb_getisordsg(z_score, p_val, p_z_sim)
+WHERE p_val <= 0.05;