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: I97780becdd452b03a45af3a98a5bd6b98aba0534
Partial-Bug: #1741634

defaults/main.yml

@@ -127,7 +127,6 @@ barbican_ssl_self_signed_subject: "/C=US/ST=Texas/L=San Antonio/O=IT/CN={{ inter
 # packages required to execute the role
 barbican_requires_pip_packages:
   - virtualenv
-  - virtualenv-tools
   - python-keystoneclient # Keystoneclient needed by OSA keystone lib
 
 # packages required to run the barbican service

tasks/barbican_install.yml

@@ -108,9 +108,12 @@
     - barbican_get_venv | changed
 
 - name: Update virtualenv path
-  command: >
-    virtualenv-tools --update-path=auto --reinitialize {{ barbican_bin | dirname }}
+  shell: |
+    find {{ barbican_bin }} -name \*.pyc -delete
+    sed -si '1s/^.*python.*$/#!{{ barbican_bin | replace ('/','\/') }}\/python/' {{ barbican_bin }}/*
   when: barbican_get_venv | changed
+  tags:
+    - skip_ansible_lint
 
 - name: Record the venv tag deployed
   ini_file: