Fixes #7588 - pagination info not a button and aligned

To properly align our pagination info label and pager we need to add a new row.
I created a helper for this. Also now on extra-small devices the info box hides
because otherwise it kinda break the end of the page. There is one snag -
sometimes we display "X items selected" there but since items are already
visually checked and since users usually do not see the whole page on small
devices, this is not an issue I think. Opinions?

This replaces https://github.com/theforeman/foreman/pull/1797

Please do not merge, this is for review. Once this is approved I will carry on
with changing all the index ERB pages (need to touch them all).