LoxiGen: start generating pyloxi 1.3

Not all classes are fully implemented.
diff --git a/py_gen/templates/common.py b/py_gen/templates/common.py
index c9af309..99d3f71 100644
--- a/py_gen/templates/common.py
+++ b/py_gen/templates/common.py
@@ -58,4 +58,9 @@
 
 :: #endfor
 
+:: if version == 1:
 match = match_v1
+:: elif version == 4:
+:: # HACK
+match = match_v3
+:: #endif