Merge pull request #28 from eriknyquist/master

SerialFlash: enlarge chip ID buffer

SerialFlashDirectory.cpp

 	// last check, if enough space exists...
 	len = strlen(filename);
 	// TODO: check for enough string space for filename
-	uint8_t id[3];
+	uint8_t id[5];
 	SerialFlash.readID(id);
 	if (address + length > SerialFlash.capacity(id)) return false;