Due to website configuration changes, every url starting with http://arduino.cc has been changed to http://www.arduino.cc. Fixes arduino#3191

Author: Federico Fissore

libraries/SPI/library.properties

@@ -4,6 +4,6 @@ author=Arduino
 maintainer=Arduino <info@arduino.cc>
 sentence=Enables the communication with devices that use the Serial Peripheral Interface (SPI) Bus. For Arduino DUE only.
 paragraph=
-url=http://arduino.cc/en/Reference/SPI
+url=http://www.arduino.cc/en/Reference/SPI
 architectures=sam
 

libraries/Wire/library.properties

@@ -4,6 +4,6 @@ author=Arduino
 maintainer=Arduino <info@arduino.cc>
 sentence=Allows the communication between devices or sensors connected via Two Wire Interface Bus. For Arduino DUE only.
 paragraph=
-url=http://arduino.cc/en/Reference/Wire
+url=http://www.arduino.cc/en/Reference/Wire
 architectures=sam