Add Moran's I local function

pg/sql/0.0.1/moran.sql

@@ -0,0 +1,22 @@
+CREATE OR REPLACE FUNCTION
+cdb_moran_local (
+    t TEXT,
+	  attr TEXT,
+	  significance float DEFAULT 0.05,
+	  num_ngbrs INT DEFAULT 5,
+	  permutations INT DEFAULT 99,
+	  geom_column TEXT DEFAULT 'the_geom',
+	  id_col TEXT DEFAULT 'cartodb_id',
+	  w_type TEXT DEFAULT 'knn'
+)
+RETURNS TABLE (
+    moran FLOAT,
+	  quads TEXT,
+	  significance FLOAT,
+	  ids INT
+)
+AS $$
+  from crankshaft.clustering import moran_local
+  -- TODO: use named parameters or a dictionary
+  return moran_local(t, attr, significance, num_ngbrs, permutations, geom_column, id_col, w_type)
+$$ LANGUAGE plpython2u;