Changes the sms log file so that new messages can be counted

The log now contains @READ@ where @ is a null byte where new and old
messages diverge. This means that new sms's can be more easily counted

This, as well as a count for missed calls, has been added to the
phoneStatus notification

bin/.bin/modem/checkSMS

@@ -61,6 +61,8 @@ echo "$ids" | while read -r id; do
 
 	log="$SMS_DIR/$number/sms.log"
 
+	[ ! -f "$log" ] && printf '\00READ\00' >> "$log"
+
 	# Store the message in the log file
 	echo "RECIEVED"
 	echo "SENDER: $number" >> $log