Add pagination to contributors

[ajax484]

Would be nice to have, in the eventuality of the number of contributors exceeding 20

[ATLAS2002]

I have addded the feature, but I can't create a new pull request unless you merge the previous one
Here is how it's going to look:

[ATLAS2002]

Hi @ajax484 , so the last time I made a pull request I actually forgot to create a new branch to add the pagination feature so I went along and kept adding it to the visibility enhancement solution. Which resulted into a single PR merge solving 2 different issues: #27 and current one. That said the pagination feature is added to the site. If you are satisfied with the pagination feature you can close this issue, or I can change it as your needs.