Adds os_images_rhel_debootstrap_enabled

Use case is when you don't want this role to modify package repos, but
you still want debootstrap.

roles/os_images/defaults/main.yml

@@ -101,3 +101,7 @@ os_images_hide: false
 
 # Visibility of images ('public' requires admin rights.)
 os_images_visibility: "{{ 'public' if os_images_public | bool else 'private' }}"
+
+# Whether or not to install debootstrap on Linux distributions in the RedHat family.
+# This allows you to build Debian based images on RedHat hosts. Requires EPEL.
+os_images_rhel_debootstrap_enabled: "{{ os_images_install_epel_repo }}"

roles/os_images/vars/RedHat.yml

@@ -1,7 +1,7 @@
 ---
 # List of package dependencies.
 os_images_package_dependencies:
-  - debootstrap
+  - "{% if os_images_rhel_debootstrap_enabled | bool %}debootstrap{% endif %}"
   - dosfstools
   - gdisk
   - "{% if os_images_git_elements | length > 0 %}git{% endif %}"