Update documentation related to Pagination

[jghinestrosa]

I recently needed to read about how pagination worked and, even though all the information was already there, I thought it could be reorganized in a way that:

• Available configuration for pagination is at the top of the page (just like the Configure templates page does)
• There are more details about how alias and filter work
• There's more context regarding some of the code examples

In my opinion, these changes could help making the docs clearer when reading them for the first time. I hope this is useful for other users. Just let me know if there's something wrong or something that might be improved.