Updated changelog

Author: cmaglie

CHANGELOG

@@ -1,4 +1,4 @@
-SAMD CORE 1.6.6
+SAMD CORE 1.6.6 2016.05.19
 
 * Fixed digitalPinToInterrupt() macro, now it works as documented.
 * Added analogInputToDigitalPin macro
@@ -8,6 +8,7 @@ SAMD CORE 1.6.6
 * Fixed Wire.write(0x00) "ambiguos method" error
 * String class now supports iterators. Thanks @Chris--A
 * Remove enabling bootloader protection when burning bootloader. This enables WDT, so sketches do not work.
+* Added remote upload for Yun-Shield
 
 SAMD CORE 1.6.5 2016.04.02