add eeprom library explicitly

digistump-avr/libraries/EEPROM/examples/eeprom_clear/eeprom_clear.ino

@@ -0,0 +1,35 @@
+/*
+ * EEPROM Clear
+ *
+ * Sets all of the bytes of the EEPROM to 0.
+ * Please see eeprom_iteration for a more in depth
+ * look at how to traverse the EEPROM.
+ *
+ * This example code is in the public domain.
+ */
+
+#include <EEPROM.h>
+
+void setup()
+{
+
+  /***
+    Iterate through each byte of the EEPROM storage.    
+    
+    Larger AVR processors have larger EEPROM sizes, E.g:
+    - Arduno Duemilanove: 512b EEPROM storage.
+    - Arduino Uno:        1kb EEPROM storage.
+    - Arduino Mega:       4kb EEPROM storage.
+    
+    Rather than hard-coding the length, you should use the pre-provided length function.
+    This will make your code portable to all AVR processors.    
+  ***/
+  
+  for ( int i = 0 ; i < EEPROM.length() ; i++ )
+    EEPROM.write(i, 0);
+
+  // turn the LED on when we're done
+  digitalWrite(13, HIGH);
+}
+
+void loop(){ /** Empty loop. **/ }