Update Http_API.md

Author: Roberto De Ioris

docs/Http_API.md

@@ -9,7 +9,7 @@ The usage is pretty 'pythonic' and support both polling and evented approaches:
 from unreal_engine import IHttpRequest
 import json
 
-request = IHttpRequest('Get', 'http://httpbin.org/user-agent')
+request = IHttpRequest('GET', 'http://httpbin.org/user-agent')
 
 def response_received(request, response, success):
     data = json.loads(response.get_content_as_string())
@@ -21,3 +21,21 @@ request.bind_on_process_request_complete(response_received)
 # run the request
 request.process_request()
 ```
+
+If you prefer the polling apparoach, you need to check for the get_status() return value (an int). In the C++ it is defined as:
+
+```c++
+namespace EHttpRequestStatus
+{
+    enum Type
+    {
+        NotStarted,
+        Processing,
+        Failed,
+        Failed_ConnectionError,
+        Succeeded,
+    }
+}
+```
+
+