Add support for http(s)_proxy to CoreOS, Fedora and OpenSUSE (#4669)

* Add support for http(s)_proxy to CoreOS and Fedora

* fix opensuse proxy support

* Fix CoreOS proxy support

* update documentation

roles/bootstrap-os/tasks/bootstrap-opensuse.yml

@@ -1,6 +1,33 @@
 ---
 # OpenSUSE ships with Python installed
 
+- name: Set the http_proxy in /etc/sysconfig/proxy
+  lineinfile:
+    path: /etc/sysconfig/proxy
+    regexp: '^HTTP_PROXY='
+    line: 'HTTP_PROXY="{{ http_proxy }}"'
+  become: true
+  when:
+    - http_proxy is defined
+
+- name: Set the https_proxy in /etc/sysconfig/proxy
+  lineinfile:
+    path: /etc/sysconfig/proxy
+    regexp: '^HTTPS_PROXY='
+    line: 'HTTPS_PROXY="{{ https_proxy }}"'
+  become: true
+  when:
+    - https_proxy is defined
+
+- name: Enable proxies
+  lineinfile:
+    path: /etc/sysconfig/proxy
+    regexp: '^PROXY_ENABLED='
+    line: 'PROXY_ENABLED="yes"'
+  become: true
+  when:
+    - http_proxy is defined or https_proxy is defined
+
 # Without this package, the get_url module fails when trying to handle https
 - name: Install python-cryptography
   zypper: