Remove requiretty from sudoers to actually make pipelining work

Some systems (e.g. CentOS on Azure) have requiretty in sudoers which makes
pipelining fail.

cluster.yml

@@ -2,6 +2,8 @@
 - hosts: all
   any_errors_fatal: true
   gather_facts: false
+  vars:
+    ansible_ssh_pipelining: false
   roles:
     - bootstrap-os
   tags:

roles/bootstrap-os/tasks/main.yml

@@ -3,4 +3,6 @@
   when: bootstrap_os == "ubuntu"
 
 - include: bootstrap-coreos.yml
-  when: bootstrap_os == "coreos"
+  when: bootstrap_os == "coreos"
+
+- include: setup-pipelining.yml

roles/bootstrap-os/tasks/setup-pipelining.yml

@@ -0,0 +1,6 @@
+---
+# Remove requiretty to make ssh pipelining work
+
+- name: Remove require tty
+  lineinfile: regexp="^\w+\s+requiretty" dest=/etc/sudoers state=absent
+