Make tabs switch between different fragments

- Construct record and history Fragments.
- Create a tab listener that attaches and detaches the tab fragments.
- Dynamically add a MapFragment to record. You cannot do this
  statically, as child fragment support in Android sucks at the moment.
- Apply some configuration to the map.
- Save map state between "configuration changes" (eg. device rotation).
Remove commented putFragment code

This was added while trying some different approaches and should've been
removed.
Clean up unused imports and indentation
Merge pull request #3 from routemaster/tabs

Make tabs switch between different fragments