Sample App Major Section: Mapping

[msmollin]

• [x] Switcher to see available basemap styles (https://github.com/mapzen/android/issues/457)
• [x] Support for theme selection if basemap has available themes (https://github.com/mapzen/android/issues/463)
• [x] Show using custom style with Tron (https://github.com/mapzen/android/issues/481)
• [ ] Locate me
• [ ] Compass widget
• [ ] Zoom buttons
• [ ] Double tap to drag and zoom
• [ ] Prompt to tilt
• [ ] Transit / Biking Overlays