Add dev vm provisioning script and documentation

As I was getting started with the project, I found I could improve the documentation on how to set up your local development environment. I then decided to wrap those complex commands in a few scripts, and bin/dev-vm was born.

It is a simple bash script that contains the necessary steps to create, destroy, and provision an Orka VM to develop on this playbook. I initially tried to set my environment up with Vagrant and a local Vmware VM but found it quite slow to work with. Additionally, by working in Orka directly, we can better mimic the production environment. Maybe in the future, we can find a Vagrant Orka provider?

For the Ansible inventory, in order to minimize authentication problems (i.e., no need to manipulate an access token), I went with the orka-cli instead of the HTTP API. This necessitates a few modifications to the existing inventory script. I wish we could find a similar solution to avoid storing GCP service account tokens locally.

Finally, this sets the always tag on facts gathering tasks since they need to run everytime, even when a user is focusing on tasks with tag filtering. Otherwise variables are undefined.