[Usability] Keyboard navigation in icon view could be easily improved

[Mateusz <mati_wroc o2 pl>]

Hello,

I was directed here from Fedora bugzilla
(https://bugzilla.redhat.com/show_bug.cgi?id=443255).

Here's my issue:

When I use right arrow to iterate over all items in a folder, it stops
at the edge of the window. It would be nice if it could move me to the
next row.
The same goes with the left arrow at the left edge: it could move to
the previous row.

Steps to Reproduce:
1. Open a folder with a large amount of files in the icon view.
2. Try to iterate over it with the keyboard.
3. See how painlful it is when you reach the edge (especially in a
maximized window on a wide screen).

Thanks,
Mateusz