Fix missing Android XML namespace reported by lint
Suppress lint warning about layout inflation without a parent

I'm not entirely convinced this is the correct course of action. Maybe I should
provide a parent view somehow? Lint refers to the following blog post on the
topic:

http://www.doubleencore.com/2013/05/layout-inflation-as-intended/

I think in the case of this strange overlay, providing a null parent is probably
acceptable, so I'm suppressing the warning for the time being.
Suppress lint warning about hardware acceleration being version dependent
Remove landscape layout definitions

These don't appear to do anything, I'm not sure why they were still around. They
don't differ from the portrait versions, so there's no reason for their
existence as far as I can tell.