Support loading old models in ML module

- added test for loading legacy files
- added version to new written models
- fixed loading of several fields in some models
- added generation of new fields from old data

modules/ml/src/ann_mlp.cpp

@@ -1241,7 +1241,7 @@ public:
         clear();
 
         vector<int> _layer_sizes;
-        fn["layer_sizes"] >> _layer_sizes;
+        readVectorOrMat(fn["layer_sizes"], _layer_sizes);
         create( _layer_sizes );
 
         int i, l_count = layer_count();