Add restrict to tiles.list

If entries are over a month ago, remove them from tiles.list

scripts/update-tile-list.sh

@@ -1,8 +1,15 @@
 #! /bin/bash
 
 LIST=tiles.list && touch $LIST
+LAST_MONTH_TIMESTAMP=$(date --date='-1 month' +%s)
 
-git status tiles/ --short | awk -v date="$(date +%s)" '{print date, $2}' | cat - $LIST >$LIST.bak
+git status tiles/ --short | awk -v date="$(date +%s)" '{print date, $2}' \
+| cat - $LIST \
+| while read timestamp tile; do
+  # remove entries that over a month ago
+  [[ $timestamp -lt $LAST_MOTH_TIMESTAMP ]] && break
+  echo $timestamp $tile
+done >$LIST.bak
 
 sort -u -k2 <$LIST.bak >$LIST
 rm $LIST.bak