Replace virtualenv-tools by a script

virtualenv-tools has a bug which gets triggered in gates: it can't
change the shebang of a virtualenv python bin/ files if they
were generated with a virtualenv script whose shebang ends with
python2 instead of python.

Because we can't modify virtualenv-tools, we use shell scripts
instead.

Change-Id: Ida7e116dc3a06b1527cc7b10065faed516c9dbb1
Partial-Bug: #1741634

defaults/main.yml

@@ -160,7 +160,6 @@ octavia_requires_pip_packages:
   - python-keystoneclient # Keystoneclient needed to OSA keystone lib
   - shade
   - virtualenv
-  - virtualenv-tools
   - python-openstackclient
 
 # Common pip packages

tasks/octavia_install.yml

@@ -111,11 +111,14 @@
     - octavia_get_venv | changed or octavia_venv_dir | changed
 
 - name: Update virtualenv path
-  command: >
-    virtualenv-tools --update-path=auto --reinitialize {{ octavia_bin | dirname }}
+  shell: |
+    find {{ octavia_bin }} -name \*.pyc -delete
+    sed -si '1s/^.*python.*$/#!{{ octavia_bin | replace ('/','\/') }}\/python/' {{ octavia_bin }}/*
   when:
     - not octavia_developer_mode | bool
     - octavia_get_venv | changed or octavia_venv_dir | changed
+  tags:
+    - skip_ansible_lint
 
 - name: Record the venv tag deployed
   ini_file: