Navigation drawer overhaul

Currently includes:
+ Refactoring of Navigation Drawer implementation
+ All previously searched soldiers are now accessible in the dropdown
+ LoginActivity now only returns ONE soldier (matched on personaId+platformId)

TODO:
- Decide what to show on HomeFragment
- Make the Navigation Drawer display the current menu selection state properly (maybe change background resource?)
- Update to use v7 version of ActionbarDrawerToggle (+Toolbar so that the navigation drawer slides over it)
- Animations for the menu toggling (when you show/hide the soldiers) ala I/O?

[WIP] @peter-budo