README: add drone.

README.md

@@ -1,15 +1,11 @@
-| Platform | Status |
+### Testing
+
+| Environment | Status |
 | -------- | ------ |
-| Linux and Mac OS X | [![Build Status](https://travis-ci.org/concurrencykit/ck.svg)](https://travis-ci.org/concurrencykit/ck)
+| Travis (Linux / Mac OS X) | [![Build Status](https://travis-ci.org/concurrencykit/ck.svg)](https://travis-ci.org/concurrencykit/ck)
+| Drone (Windows) | [![Build Status](https://cloud.drone.io/api/badges/concurrencykit/ck/status.svg)](https://cloud.drone.io/concurrencykit/ck)
 
-```
-  ____                                                        _  ___ _
- / ___|___  _ __   ___ _   _ _ __ _ __ ___ _ __   ___ _   _  | |/ (_) |_
-| |   / _ \| '_ \ / __| | | | '__| '__/ _ \ '_ \ / __| | | | | ' /| | __|
-| |__| (_) | | | | (__| |_| | |  | | |  __/ | | | (__| |_| | | . \| | |_
- \____\___/|_| |_|\___|\__,_|_|  |_|  \___|_| |_|\___|\__, | |_|\_\_|\__|
-                                                      |___/
-```
+### Build
 
 * Step 1.  
         `./configure`  
@@ -24,4 +20,3 @@
 	To uninstall use `make uninstall`.  
 
 See http://concurrencykit.org/ for more information.
-