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: Ic2497f23d0c0a9160fc3fe57ccdb78094d499f83
Partial-Bug: #1741634

defaults/main.yml

@@ -185,7 +185,6 @@ heat_plugin_dirs:
 # Heat packages that must be installed before anything else
 heat_requires_pip_packages:
   - virtualenv
-  - virtualenv-tools
   - python-keystoneclient # Keystoneclient needed to OSA keystone lib
   - httplib2
 

tasks/heat_install.yml

@@ -109,9 +109,13 @@
     - heat_get_venv | changed
 
 - name: Update virtualenv path
-  command: >
-    virtualenv-tools --update-path=auto --reinitialize {{ heat_bin | dirname }}
+  shell: |
+    find {{ heat_bin }} -name \*.pyc -delete
+    sed -si '1s/^.*python.*$/#!{{ heat_bin | replace ('/','\/') }}\/python/' {{ heat_bin }}/*
+    virtualenv {{ heat_bin | dirname }}
   when: heat_get_venv | changed
+  tags:
+    - skip_ansible_lint
 
 - name: Record the venv tag deployed
   ini_file: