Add feature to remove cached icons when spinning down project

The changes in this commit ensures that cached icons are removed from the server
so that changes made to the `net.unraid.docker.icon` are respected.

source/compose.manager/scripts/compose.sh

@@ -1,21 +1,28 @@
 #!/bin/bash
 
 export HOME=/root
-export DOCKER_JSON=/usr/local/emhttp/state/plugins/dynamix.docker.manager/docker.json
+DOCKER_MANAGER=/usr/local/emhttp/state/plugins/dynamix.docker.manager
+DOCKER_JSON=$DOCKER_MANAGER/docker.json
+DOCKER_IMAGES=$DOCKER_MANAGER/images
+UNRAID_IMAGES=/var/lib/docker/unraid/images
 
 case $1 in
 
   up)
     docker compose -f "$2" -p "$3" ps -a |
       awk '{if (NR!=1) {printf("%s.\"%s\"", sep, $1); sep=", "}}' |
       xargs -0 -I {} jq 'del({})' $DOCKER_JSON > $DOCKER_JSON
+    docker compose -f "$2" -p "$3" ps -a |
+      xargs -I {} find $DOCKER_IMAGES $UNRAID_IMAGES -name {}.png -delete
     docker compose -f "$2" -p "$3" up -d 2>&1
     ;;
 
   down)
     docker compose -f "$2" -p "$3" ps -a |
       awk '{if (NR!=1) {printf("%s.\"%s\"", sep, $1); sep=", "}}' |
       xargs -0 -I {} jq 'del({})' $DOCKER_JSON > $DOCKER_JSON
+    docker compose -f "$2" -p "$3" ps -a |
+        xargs -I {} find $DOCKER_IMAGES $UNRAID_IMAGES -name {}.png -delete
     docker compose -f "$2" -p "$3" down  2>&1
     ;;