feat(docs): add documentation about the application (en-US)

[hmartiins]

Documenting the application

The PeruibeTec team is continuing to document its application. Our aim is to have the entire application documented, thus clarifying any doubts about the application's architecture, routes or features. First we will document the application in English, as it is the main language of the repository (as described in CONTRIBUTING.MD) and after that, we will translate this documentation to Portuguese (pt-br), as it is our native language

How to contribute to the creation of the documentation?

You can contribute in different ways to the PeruibeTec server documentation, you can:

1. Correct spelling mistakes;
2. Point out possible improvements to the documentation;
3. Documenting something you deem important to be documented

Before performing any of these steps, create an Issue, or be responsible for an Issue already created (if you have questions on how to create an issue, see CONTRIBUTING.md)

Creating my documentation file

If you're not from PeruibeTec's core, and want to create a file documenting something, follow these steps:

0. Create an issue with a documentation label
1. Within this Issue, say what your idea of ​​documentation is
2. Wait for a moderator to approve your idea (the moderator can disapprove or suggest changes to the idea)
3. After approval, create a Fork of this repository for your user
4. Create a branch on your fork called yourusername-en-documentation-yourideia (example: hmartiins-en-documentation-architeture-for-project)
5. push to your fork, with the created file
6. Create a new Pull Request in this repository, and the title should be feat(docs): English documentation <your documentation>
7. Within Pull Request, check @hmartiins, @PocketLocked and @devLeSilverio, so we can review
8. If everything is OK, congratulations your documentation is now part of PeruibeTec 🎉

If you still have any doubt, comment it here in this Issue, your doubt may be the doubt of other people too..