Transfer HTTP client examples to lua_examples/

Fixes nodemcu#941

lua_examples/http-client.lua

@@ -0,0 +1,40 @@
+-- Support HTTP and HTTPS, For example
+-- HTTP POST Example with JSON header and body
+http.post("http://somewhere.acceptjson.com/",
+    "Content-Type: application/json\r\n",
+    "{\"hello\":\"world\"}",
+    function(code, data)
+        print(code)
+        print(data)
+    end)
+
+-- HTTPS GET Example with NULL header
+http.get("https://www.vowstar.com/nodemcu/","",
+    function(code, data)
+        print(code)
+        print(data)
+    end)
+-- You will get
+-- > 200
+-- hello nodemcu
+
+-- HTTPS DELETE Example with NULL header and body
+http.delete("https://10.0.0.2:443","","",
+    function(code, data)
+        print(code)
+        print(data)
+    end)
+
+-- HTTPS PUT Example with NULL header and body
+http.put("https://testput.somewhere/somewhereyouput.php","","",
+    function(code, data)
+        print(code)
+        print(data)
+    end)
+
+-- HTTP RAW Request Example, use more HTTP/HTTPS request method
+http.request("http://www.apple.com:80/library/test/success.html","GET","","",
+    function(code, data)
+        print(code)
+        print(data)
+    end)