Implemented SampleDAO
Bug fix: getDatabase() is called recursively
Refactored Map and MapDataSource
Add model and DAO for Location History
Merge branch 'master' of https://github.com/CMUPracticum/TrailScribe

Conflicts:
	TrailScribe/src/edu/cmu/sv/trailscribe/dao/DataSource.java
Fix: SynchronizationCenterActivity extends BaseActivity now
UI Improvement: Remove title bar from MapsActivity
Merge branch 'master' of https://github.com/CMUPracticum/TrailScribe
Fix sync center map instance and update PKs for seed data in LocationHistoryDataSource
Merge branch 'master' of https://github.com/CMUPracticum/TrailScribe
Renamed LocationHistory to Location; Implemented: load samples and location history from database
Fix: generate primary key automatically
Merge remote-tracking branch 'cmu/master'