i3, screen-lock: the session's output to the journal, and the colour locker removed before i3lock is checked

lemurs leaves the session a stdout nobody reads, so a program writing to it dies of EPIPE.
i3lock-color provides i3lock, so with it still installed the host saw i3lock as present,
skipped the install and then removed the only locker; removing it first lets the same
apply install i3lock.

modules/screen-lock/module.json

@@ -29,16 +29,6 @@
     }
   ],
   "resources": [
-    {
-      "id": "watcher",
-      "type": "package",
-      "package": "xss-lock"
-    },
-    {
-      "id": "locker",
-      "type": "package",
-      "package": "i3lock"
-    },
     {
       "id": "colour-locker",
       "type": "package",
@@ -51,6 +41,16 @@
       "package": "xscreensaver",
       "absent": true
     },
+    {
+      "id": "watcher",
+      "type": "package",
+      "package": "xss-lock"
+    },
+    {
+      "id": "locker",
+      "type": "package",
+      "package": "i3lock"
+    },
     {
       "id": "wrapper",
       "type": "file",