Update support library to v4, and minSdkVersion to 7
so we can use the appcompat library.

Obsolete the ui/widgets/backport directory and its PopupMenu,
in favor of the one from appcompat.

Doesn't quite compile due to attribute name conflict in themes.
Fix resource name conflict compilation issue, following cketti's suggestion.

Use shopping_divider for compiled-in themes, but if it is not found (e.g. previously published themes) check for divider as well.
Switch from FragmentActivity to its subclass ActionBarActivity.

The PopupMenu implementation inside the appcompat library won't work without it -- it depends on some theme attributes that go with Theme.AppCompat.

Now we can start thinking about how to actually use the action bar...
Implement app drawer for list switching.

Need to fix updating app title when switching between lists or modes. Also, in the GB emulator, the list items are showing in black on grey. But it's a start.
Update action bar title and subtitle.
Fix styling of drawer menu items.

Now they are large enough, and they are visible even if
the active shopping list theme is Basic Colors (Blue).
Option to save separate sort order for each list.

When enabled, a sort menu appears in the action bar.
If Pick Items is configured to use a separate sort order from
regular shopping mode, the per-list sort order does not apply
to Pick Items, and the sort menu does not appear in Pick Items mode.
Export content providers. SDK 18.
also switch api level in project.properties
Fix price display when tag display is enabled.
Fix using sort for correct list when switching lists.
Tentatively move Pick Items, Shopping, New List to the drawer.

Needs some cosmetic work.
Merge recent changes from master
classpath updated by new adt release
Borrow some radio button pngs from AOSP.
Clean up drawer styling.

It was always my intention to make our drawer layout look similar to
the drawer in the Gmail app, but I couldn't figure out how to do
it... until the AOSP KitKat source was released with a UnifiedEmail
app following the same style. Thanks Google!
Make "Pick items directly in list" the default.

Comment out the preference. The other way-- as a pop-up dialog--
doesn't look right with the new action bar UI and doesn't have any
known advantages.
Borrow AOSP ActionableToastBar.java
Borrowed more undo-related resources from AOSP UnifiedEmail.
Modify borrowed undo code to compile in our code base.