This ensures the update list presented to the user is ready-to-go and means we
don't have to manually check the offline update is ready to go after the user
presses the button.

If you're not using the systemd-updates offline updates functionality you
probably want to be using the old packagekit-updates plugin instead.

We'll want to do something different with this in the future.

Move the 'installed' tag further down, so the icon is not
entirely obscured by it.

Move the summary and title closer together.

Use the same approach we are using for the picks, placing
the text 'Installed' on a blue background as an overlay.
The placement of the overlay still needs some fine-tuning.

https://bugzilla.gnome.org/show_bug.cgi?id=707613

Limit the width of the text. Allan asked for 620px, but since
GTK+ label operates in terms of characters, I just made it 80
characters. Also tweak to padding to follow Allans recommendations.
Lastly, move the styling of the title to css, by adding style
classes for application-details-title, -summary and -description.

https://bugzilla.gnome.org/show_bug.cgi?id=707319

The few random apps that we care about have had category overrides.

MATE may want to do set something like 'GNOME_SOFTWARE_COMPATIBLE_PROJECTS=MATE'

...but never show a 'Remove' button in this case.

This really makes working out what application to blacklist much easier.

This fixes a WARNING on the console when searching for system apps.

Arrange things so that Tab moves focus from the subcategory list
to the application grid, and make Page Up/Down page the application
grid, regardless where the focus is.

https://bugzilla.gnome.org/show_bug.cgi?id=708308

Moving the 'featured' subcategories to the first position
automatically makes them selected initially, which is the
intended effect.

https://bugzilla.gnome.org/show_bug.cgi?id=708295

Since we don't have popularity data yet, we add a
hardcoded 'featured' subcategory to each category,
and populate it with some hand-picked samples.

The samples were chosen by Jon Mccann.

We move this to the beginning of the list, so that other
plugins can add subcategories to the main categories that
this plugin creates.

That seems fitting, since it is 'everything else'.

This is the 'leftover' subcategory, and 'Other' is a more
fitting name for it.

https://bugzilla.gnome.org/show_bug.cgi?id=707550

There was a leftover reference to the old name of the box
on the overview page. Fix that.

Move the subcategory list up a bit to line it up with
the application tiles on the right.

Don't abort in the appdata plugin if data is missing.
In the UI, we hide empty sections of the overview, and if
the entire overview is empty, we show a placeholder.

https://bugzilla.gnome.org/show_bug.cgi?id=708299

Give all remaining space to the last child. This avoid
fittsiness issues in the category view.

https://bugzilla.gnome.org/show_bug.cgi?id=708307

The app name is just 'Software'.

https://bugzilla.gnome.org/show_bug.cgi?id=708314

Make sure all the headings have the same padding.

We're not all mclasen... :)

Use focus vadjustment functionality in GTK+ to ensure that all
out scrolled windows keep the focus widget on screen.

https://bugzilla.gnome.org/show_bug.cgi?id=708183