Updated sam core version to 1.6.5

Author: cmaglie

hardware/arduino/sam/platform.txt

@@ -6,7 +6,7 @@
 # https://github.com/arduino/Arduino/wiki/Arduino-IDE-1.5-3rd-party-Hardware-specification
 
 name=Arduino ARM (32-bits) Boards
-version=1.6.4
+version=1.6.5
 
 # SAM3 compile variables
 # ----------------------