Improve docs & Add JSON decode example (#121)

test/srt/test_curl.sh

@@ -0,0 +1,9 @@
+curl http://localhost:30000/generate \
+  -H "Content-Type: application/json" \
+  -d '{
+    "text": "Once upon a time,",
+    "sampling_params": {
+      "max_new_tokens": 16,
+      "temperature": 0
+    }
+  }'