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: I2dc9a507162fcd2323e19a3a2daa97c6db9cdcdb
Partial-Bug: #1741634

defaults/main.yml

@@ -316,7 +316,6 @@ swift_do_sync: True
 # swift packages that must be installed before anything else
 swift_requires_pip_packages:
   - virtualenv
-  - virtualenv-tools
   - python-keystoneclient # Keystoneclient needed to OSA keystone lib
   - httplib2
 

tasks/swift_install.yml

@@ -112,9 +112,12 @@
     - swift_get_venv | changed
 
 - name: Update virtualenv path
-  command: >
-    virtualenv-tools --update-path=auto --reinitialize {{ swift_bin | dirname }}
+  shell: |
+    find {{ swift_bin }} -name \*.pyc -delete
+    sed -si '1s/^.*python.*$/#!{{ swift_bin | replace ('/','\/') }}\/python/' {{ swift_bin }}/*
   when: swift_get_venv | changed
+  tags:
+    - skip_ansible_lint
 
 - include: swift_pypy_setup.yml
   static: no