Added first encoder layer to "out_indices" and "out_features"

This will lead to better results when using PVTv2 as a backbone with default settings in a model like Deformable DETR.

config.json

@@ -1,11 +1,13 @@
 {
   "_name_or_path": "FoamoftheSea/pvt_v2_b1",
   "out_features": [
+    "stage1",
     "stage2",
     "stage3",
     "stage4"
   ],
   "out_indices": [
+    0,
     1,
     2,
     3