Create the wiki for the infrastructure template

[longnd]

Why

The infrastructure-template is a useful tool for generating infrastructure code for a new project. However, its documentation is very minimal and lacks instructions on the architecture of the template, how to contribute, and how to use a newly generated project.

This lack of documentation limits contributions from the team, for instance, the recent refactor in the template, as seen in #169 (comment), may be difficult for any team member to understand without any technical documentation.

Who Benefits?

The web chapter & the outside contributors can contribute to the infrastructure-template easier.