Upgrade kf_config.json to v2 (nested config + weight_dtype)

kf_config.json

@@ -1,34 +1,46 @@
 {
   "library_name": "kerasformers",
-  "kerasformers_version": "1.1.3",
+  "kerasformers_version": "1.2.1",
   "model_module": "kerasformers.models.mobilevit",
   "model_class": "MobileViTImageClassify",
   "variant": "mobilevit_s_cvnets_in1k",
   "weights": "model.weights.h5",
+  "schema_version": 2,
+  "weight_dtype": "float32",
   "model_type": "mobilevit",
-  "initial_dims": 16,
-  "head_dims": 640,
-  "block_dims": [
-    32,
-    64,
-    96,
-    128,
-    160
-  ],
-  "expansion_ratio": [
-    4.0,
-    4.0,
-    4.0,
-    4.0,
-    4.0
-  ],
-  "attention_dims": [
-    null,
-    null,
-    144,
-    192,
-    240
-  ],
-  "image_size": 256,
-  "num_classes": 1000
+  "vision_config": {
+    "initial_dims": 16,
+    "head_dims": 640,
+    "block_dims": [
+      32,
+      64,
+      96,
+      128,
+      160
+    ],
+    "expansion_ratio": [
+      4.0,
+      4.0,
+      4.0,
+      4.0,
+      4.0
+    ],
+    "attention_dims": [
+      null,
+      null,
+      144,
+      192,
+      240
+    ],
+    "image_size": 256,
+    "num_classes": 1000,
+    "output_stride": 32,
+    "atrous_rates": [
+      6,
+      12,
+      18
+    ],
+    "aspp_out_channels": 256,
+    "aspp_dropout_prob": 0.1
+  }
 }