Remove most uses of egg-list-box in a dumb way

Ideally, we should be setting things on the GtkListBoxRow directly,
rather than doing this.
network: Simplify code
network: Skip page if we're already connected
gis-assistant: Hide page in the progress indicator if it's invisible
Do a simple first design update pass

Add the icons, adopt new headings and text to network, summary and goa,
but don't do any actual content changes yet. Those will come later.
Rename the location page to timezone

This is how it will behave in the new design. This doesn't have any
design updates yet; wanted to get the file renaming out of the way.
Put GOA page before accounts

And fix up the order in the rest of the files
Rework skipping pages mechanism a bit
goa: Adapt to new page design