Resist to None values in the pillar
Some comments
-{% set proxy_systemwide = salt.caasp_pillar.get('proxy:systemwide', False) %}
-
-{% if proxy_systemwide %}
+{% if salt.caasp_pillar.get('proxy:systemwide') %}
{% set proxy_http = salt.caasp_pillar.get('proxy:http') %}
{% set proxy_https = salt.caasp_pillar.get('proxy:https') %}
