Add model configuration

config.json

@@ -0,0 +1,9 @@
+{
+    "vocab_size": 50257,
+    "context_length": 256,
+    "emb_dim": 768,
+    "n_heads": 12,
+    "n_layers": 12,
+    "drop_rate": 0.1,
+    "qkv_bias": false
+}