Refactor downloads to use download role directly (#1824)

* Refactor downloads to use download role directly

Also disable fact delegation so download delegate works acros OSes.

* clean up bools and ansible_os_family conditionals

roles/kubespray-defaults/defaults/main.yaml

@@ -132,6 +132,8 @@ kubectl_localhost: false
 # K8s image pull policy (imagePullPolicy)
 k8s_image_pull_policy: IfNotPresent
 efk_enabled: false
+helm_enabled: false
+istio_enabled: false
 enable_network_policy: false
 
 ## When OpenStack is used, Cinder version can be explicitly specified if autodetection fails (https://github.com/kubernetes/kubernetes/issues/50461)

roles/kubespray-defaults/meta/main.yml

@@ -0,0 +1,6 @@
+---
+dependencies:
+  - role: download
+    skip_downloads: true
+    tags:
+      - facts