Improve multiple templates tutorial

It doesn't explain how to create multiple templates. It focuses on how to map and switch from one to another.

[Read online ](https://docs.hi-framework.org/1.0.0/tutorials/category/templates/multiple-templates.html)

[Edit on Github](https://github.com/Emerjoin/Hi-Framework-docs/blob/1.0.0/tutorials/docs-project/category/02_templates/02_multiple-templates.md)