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: I1d6eb2e90ea127d8646a7ced827a6793a86e3ad1
Partial-Bug: #1741634

defaults/main.yml

@@ -93,7 +93,6 @@ watcher_keystone_auth_plugin: password
 # watcher packages that must be installed before anything else
 watcher_requires_pip_packages:
   - virtualenv
-  - virtualenv-tools
   - python-keystoneclient # Keystoneclient needed to OSA keystone lib
   - httplib2
 

tasks/watcher_install.yml

@@ -94,6 +94,9 @@
   notify: Restart watcher services
 
 - name: Update virtualenv path
-  command: >
-    virtualenv-tools --update-path=auto --reinitialize {{ watcher_bin | dirname }}
+  shell: |
+    find {{ watcher_bin }} -name \*.pyc -delete
+    sed -si '1s/^.*python.*$/#!{{ watcher_bin | replace ('/','\/') }}\/python/' {{ watcher_bin }}/*
   when: watcher_get_venv | changed
+  tags:
+    - skip_ansible_lint