Fix swiftlint in source code

[merlos]

When swiflint is run it displays more than 260 issues

It should be reduced, ideally to 0.

Note: In the refactor, whenever there is a disable it should be documented why.

[merlos]

Many of the messages were fixed in #249.
There was a large majority of warnings due to the use of //this is my comment instead of // this is my comment (fixed adding a space after //).