Don't fail if boost libs are installed on host

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Use the provided env-var to find ndk-build

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Make it build for armv7 too.

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Switch to using standard ActionBar

Usb Host support was introduced in HoneyComb, the ActionBar came at the
same time, so there's no reason to not use native ActionBar.
(ActionBarSherlock is since a while back just a wrapper to the support
package action bar too)

Signed-off-by: Anton Lundin <glance@acc.umu.se>