bootstrap: rework role (#4045)

* bootstrap: rework role

* support being called from a non-root user
* run some commands in check mode
* unify spelling/task names

* bootstrap: fix wording of comments for check_mode: false

* bootstrap: remove setup-pipelining task

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

@@ -1,5 +1,5 @@
 ---
-- name: check if atomic host
+- name: Check if atomic host
   stat:
     path: /run/ostree-booted
   register: ostree
@@ -19,24 +19,25 @@
     regexp: "^enabled=.*"
     line: "enabled=0"
     state: present
+  become: true
   when: fastestmirror.stat.exists
 
 - name: Add proxy to /etc/yum.conf if http_proxy is defined
   lineinfile:
     path: "/etc/yum.conf"
-    line: "proxy={{http_proxy}}"
+    line: "proxy={{ http_proxy }}"
     create: yes
     state: present
+  become: true
   when: http_proxy is defined
 
 - name: Install libselinux-python and yum-utils for bootstrap
   yum:
-    name: "{{ packages }}"
-    state: present
-  vars:
-    packages:
+    name:
       - libselinux-python
       - yum-utils
+    state: present
+  become: true
   when:
     - not is_atomic
 
@@ -51,6 +52,7 @@
   yum:
     name: epel-release
     state: present
+  become: true
   when:
     - epel_enabled
     - not is_atomic
@@ -82,6 +84,7 @@
   yum:
     name: python-pip
     state: present
+  become: true
   when:
     - not is_atomic
     - package_python_pip.results | length != 0