Store fewer snapshots for downloads directory

ansible/group_vars/all/sanoid.yml

@@ -2,6 +2,11 @@ sanoid_datasets:
   tank:
     use_template: production
     recursive: true
+
+  tank/downloads:
+    use_template: replaceable
+    recursive: true
+
 sanoid_templates:
   production:
     frequently: 0
@@ -11,3 +16,12 @@ sanoid_templates:
     yearly: 0
     autosnap: true
     autoprune: true
+
+  replaceable:
+    frequently: 0
+    hourly: 6
+    daily: 2
+    monthly: 0
+    yearly: 0
+    autosnap: true
+    autoprune: true