Make it easy to build and deploy

Ideally, this means creating a Makefile that can do the following:

1. Build www_alum
2. Generate a tarsnap key
3. Generate smtpd.pem

We should also have documentation that makes it apparent how to set up a new instance of alum from scratch on your local computer. Something like:

> On your development computer:
>
> 1. Install Go version X.Y.Z and ansible-playbook.
> 2. `make tarsnap.key`
> 3. `make smtpd.pem`
> 4. `make www_alum` and uncomment the www_alum role
> 5. Edit inventory.ini
> 6. `ansible-playbook ...`

Start by reviewing the requested Makefile targets for building www_alum, generating tarsnap.key, and generating smtpd.pem, then inspect inventory.ini, the www_alum role, and the existing ansible-playbook entry point. Done means a new local instance can follow the documented sequence from dependency installation through build, configuration, and deployment.

Written by the indexing model from the issue text.