Add auto-formatter

[luizinhosuraty]

Description

We have a few issues regarding the code style. We are not following any and we should start to follow one ASAP to provide ways for creating less error-prone and more maintainable software.

Proposal

We need to add an auto-formatter.

And this auto-formatter should run just before each push, to verify the style consistency.

Links / references

http://astyle.sourceforge.net/

https://clang.llvm.org/docs/ClangFormatStyleOptions.html