Add ensure-twine role

Change-Id: Ic00e4f0c08fc42ce9d68f39be8522b6c2bba6396

roles/ensure-twine/tasks/main.yaml

@@ -0,0 +1,18 @@
+- name: Check for twine install
+  command: which twine
+  ignore_errors: yes
+  register: register_twine
+
+- name: Set pypi_twine_executable
+  set_fact:
+    pypi_twine_executable: "{{ register_twine.stdout }}"
+  when: register_twine|succeeded
+
+- name: Ensure twine is installed
+  command: pip install twine --user
+  when: pypi_twine_executable is not defined
+
+- name: Set pypi twine executable
+  set_fact:
+    pypi_twine_executable: ~/.local/bin/twine
+  when: pypi_twine_executable is not defined