Allow overrides of bootstrap ansible script

Some providers may have a different bootstrapping script,
and probably want to use their own instead of always
bootstrapping the OSA one for the leap.

We should be able to give a script as env var, and use
that script for installing an ansible that works for leapfrog.

Change-Id: I034d3dace52ae092e04d4573c6299b464153084d

leap-upgrades/lib/functions.sh

@@ -97,7 +97,15 @@ function run_lock {
   set -e
 }
 
-function system_bootstrap {
+function bootstrap_recent_ansible {
+    # This ensures that old ansible will be removed
+    # and that we have a recent enough Ansible version for:
+    # - the variable upgrades
+    # - the db migrations
+    # - the host upgrade
+    # - the neutron container forget
+    # - the re deploy, if there was no hook that
+    #   redeployed ansible
     if [[ -d "/opt/ansible-runtime" ]]; then
       rm -rf "/opt/ansible-runtime"
     else
@@ -117,7 +125,7 @@ function system_bootstrap {
       notice "Removed System installed Ansible"
     done
 
-    pushd "$1"
+    pushd "${BOOTSTRAP_ANSIBLE_FOLDER}"
       # Install ansible for system migrations
       scripts/bootstrap-ansible.sh
     popd

leap-upgrades/lib/vars.sh

@@ -40,6 +40,9 @@ export VALIDATE_UPGRADE_INPUT="${VALIDATE_UPGRADE_INPUT:-TRUE}"
 export UPGRADES_TO_TODOLIST="${UPGRADES_TO_TODOLIST:-''}"
 export CODE_UPGRADE_FROM=""
 
+# Bootstrap ansible tool, see also bootstrap_recent_ansible
+export BOOTSTRAP_ANSIBLE_FOLDER=${BOOTSTRAP_ANSIBLE_FOLDER:-/opt/openstack-ansible/}
+
 ## Ansible debugging
 export LEAP_TIMESTAMP=$(date +%s)
 export ANSIBLE_LOG_PATH="/opt/leap42/ansible-${LEAP_TIMESTAMP}.log"

leap-upgrades/prep.sh

@@ -73,6 +73,6 @@ if [[ ! -f "/opt/leap42/openstack-ansible-prep-finalsteps.leap" ]]; then
     unset ANSIBLE_INVENTORY
 
     link_release "/opt/leap42/openstack-ansible-${NEWTON_RELEASE}"
-    system_bootstrap "/opt/openstack-ansible"
+    bootstrap_recent_ansible
     touch "/opt/leap42/openstack-ansible-prep-finalsteps.leap"
 fi