Move application delegate to Application group

Most of the UI and application related code will be located in a
separate group, here called Application. Move the application delegate
there to start with.

Signed-off-by: Marcus Karlsson <mk@acc.umu.se>
Move resources to Resources group

Resources are spread across the repository. Improve the organization by
moving them to a dedicated group called Resources.

Signed-off-by: Marcus Karlsson <mk@acc.umu.se>