Merge pull request #52 from metakermit/patch-1

add post message example to the README

Author: Leah Jones

README.md

@@ -41,6 +41,10 @@ token = "xoxp-28192348123947234198234"      # found at https://api.slack.com/web
 sc = SlackClient(token)
 print sc.api_call("api.test")
 print sc.api_call("channels.info", channel="1234567890")
+print sc.api_call(
+    "chat.postMessage", channel="#general", text="Hello from Python! :tada:",
+    username='pybot', icon_emoji=':robot_face:'
+)
 ```
 
 ### Real Time Messaging