docs: automation

fixes: #1

docs/admin/install.rst

@@ -0,0 +1,25 @@
+Installation
+============
+
+The current installation method is to use a Python virtual envrionment.
+Many of the dependencies needed by the portal can be installed from PyPI, although some
+dependencies will need to be satisfied in other ways:
+
+* A cron daemon - probably available in your system package manager
+* Terraform binary - static binaries available from Hashicorp
+* PostgreSQL server - probably available in your system package manager
+
+Create and activate a virtual environment with:
+
+.. code-block:: shell
+
+   cd /installation/directory
+   python -m venv env
+   . env/bin/activate
+
+You will need to install an entry into the portal user's crontab:
+
+.. code-block:: crontab
+
+   */1 * * * * (cd /path/to/portal ; /path/to/env/bin/python -m app.cli automate --all) &>/dev/null
+