roles/taiga: Deploy Taiga project management app

The *taiga* role installs the three components of Taiga:

* taiga-back
* taiga-events
* taiga-front

*taiga-back* is a Python application. Its dependencies are installed via
`pip` in the *taiga* user's site-packages, and the application itself is
installed by unpacking the archive. *taiga-events* is a Node.js
application. Its dependencies are installed by `npm`, and is itself
installed by unpacking the archive. Finally, *taiga-front* is a
single-page browser application that is installed by unpacking the
archive, and served by Apache.

Taiga requires PostgreSQL and RabbitMQ.

roles/taiga/tasks/taiga-front.yml

@@ -0,0 +1,11 @@
+- name: ensure taiga-front is installed
+  unarchive:
+    src: '{{ taiga_front_url }}'
+    dest: /usr/local/lib/taiga/
+    remote_src: true
+
+- name: ensure taiga-front is configured
+  template:
+    src: taiga-front.conf.json.j2
+    dest: /usr/local/lib/taiga/taiga-front-dist/dist/conf.json
+    mode: '0644'