Handle multiple os_family vars in single file

[asteen27]

Problem

When using this role inside other roles on distributions like Ubuntu it seems redundant to have to specify the default vars again since vars use "{{ ansible_distribution }}.yml" or "{{ ansible_os_family }}.yml" before default.yml.

Solution

Handle vars inside vars/main.yml instead of a separate task looping in var files.

Testing

Worked to install and configure sudo(8) on FreeBSD 12.1 and Ubuntu 18.04