Plugin Install Pagination on small screens needs padding

[Ipstenu]

Props to @acreativecollective for spotting this: ​http://wordpress.org/support/topic/plugin-installphp-pagination-missing-margin-top?replies=1

Full screen: ​https://cloudup.com/cNLRY45Js6L
Small screen: ​https://cloudup.com/czqO4ted6Lx

There's a need for padding on that media size.

Patch attached

[Ipstenu]

CSS change

[stephdau]

A Different take on the fix, as an option.

[stephdau]

I've tried your patch, and it looks great, fixes the bug listed on this ticket. See ​https://cloudup.com/co88KoMmRFr

On the other hand, I checked where else .tablenav.top (list-tables) is used, and it looks like we usually go for more room around the navbar (though never really with symmetrical top and border margins anywhere)

attachment:29369.2.diff​ addresses the top margin issue in the plugins search results, but also homogenizes the toolbar in other instances (IMHO). See ​https://cloudup.com/cVLcfAQRY5I

[stephdau]

Note: both patches still apply fine after r29625.

Mine: ​https://cloudup.com/cIP4ct5K6y9

ipstenu's: ​https://cloudup.com/cIJg5_JSk-d

[helen]

In 29627:

Give pagination controls some breathing room on smaller screens.

props stephdau.
fixes #29369.

[stephdau]

#29279 was marked as a duplicate.