Refactor and new tests

pg/test/0.0.1/sql/02_moran_test.sql

@@ -0,0 +1,12 @@
+\i test/fixtures/ppoints.sql
+
+-- Moral functions perform some nondeterministic computations
+-- (to estimate the significance); we will set the seeds for the RNGs
+-- that affect those results to have repeateble results
+SELECT cdb_crankshaft.cdb_random_seeds(1234);
+
+SELECT ppoints.code, m.quads
+  FROM ppoints
+  JOIN cdb_crankshaft.cdb_moran_local('ppoints', 'value') m
+    ON ppoints.cartodb_id = m.ids
+  ORDER BY ppoints.code;