Merge pull request #175 from quantumlicht/master

Add documentation for top level API in README

README.md

@@ -31,6 +31,39 @@ a WebSocket Server and Client for Arduino based on RFC6455.
  - ATmega2560 with Ethernet Shield (ATmega branch)
  - ATmega2560 with enc28j60 (ATmega branch)
 
+##### High Level API #####
+
+ - `begin` : Initiate connection sequence to the websocket host.
+```
+void begin(const char *host, uint16_t port, const char * url = "/", const char * protocol = "arduino");
+void begin(String host, uint16_t port, String url = "/", String protocol = "arduino");
+ ```
+ - `onEvent`: Callback to handle for websocket events
+
+ ```
+ void onEvent(WebSocketClientEvent cbEvent);
+ ```
+
+ - `WebSocketClientEvent`: Handler for websocket events
+ ```
+ void (*WebSocketClientEvent)(WStype_t type, uint8_t * payload, size_t length)
+ ```
+Where `WStype_t type` is defined as:
+  ```
+  typedef enum {
+      WStype_ERROR,
+      WStype_DISCONNECTED,
+      WStype_CONNECTED,
+      WStype_TEXT,
+      WStype_BIN,
+  	WStype_FRAGMENT_TEXT_START,
+  	WStype_FRAGMENT_BIN_START,
+  	WStype_FRAGMENT,
+  	WStype_FRAGMENT_FIN,
+  } WStype_t;
+  ```
+
+
 ###### Note: ######
 
   version 2.0 and up is not compatible with AVR/ATmega, check ATmega branch.