Implement alternative layouts for xhdpi and hdpi

For some reason the views don't scale properly for xhdpi and hdpi screen
resolutions and therefore I needed to provide alternative layouts for
these types of densities. Also decided not to mess with landscape layout
for now.

- Provide "supports screens" attribute to the Manifest file.
- Add the screenOrientation attribute to the manifest, so that the app
  only displays in portrait mode for now.
- Provide alternative layouts for xhdpi and hdpi portrait mode.
- Modify progress fragment layout files, so that they would look nice and
neat in all densities.