Created DB* classes
Added DBReader-methods
Implemented DBWriter-methods
Implemented several DBTasks and DBWriter methods
Split DownloadStatus into two separate classes

DownloadStatus is now used only for finished downloads, whereas
DownloadRequest is used for running/unfinished downloads
Implemented refresh, auto-download, auto-cleanup methods
Added search methods to DBTasks
Ported several classes from FeedManager to DB*-classes
Organizing the queue now works, several bugfixes etc.
Improved DownloadService, several bugfixes

- DownloadService should now terminate properly as soon as all downloads have been completed.
- Notification bug ("0 downloads left" notification) should be fixed
Ported playback service to DB* classes
Ported PlaybackController to DB*-classes
Ported playback classes to DB* classes
Ported search components to DB*-classes
Removed last references to FeedManager
Added FeedItemStatistics.

Makes it possible to get number of (new, in progress) episodes of a feed without loading the whole list of items
Removed FeedManager

DBReader, DBTasks and DBWriter should be used instead from now on
Do not display empty listview message while loading
Merge branch 'develop' into feedmanager_removal

Conflicts:
	src/de/danoeh/antennapod/activity/PreferenceActivity.java
	src/de/danoeh/antennapod/feed/FeedManager.java
	src/de/danoeh/antennapod/service/PlaybackService.java
	src/de/danoeh/antennapod/service/download/DownloadService.java
	src/de/danoeh/antennapod/service/download/DownloadStatus.java
	src/de/danoeh/antennapod/service/download/HttpDownloader.java
	src/de/danoeh/antennapod/storage/DownloadRequester.java
	src/de/danoeh/antennapod/storage/PodDBAdapter.java
	src/de/danoeh/antennapod/util/playback/PlaybackController.java
Refresh lock was used incorrectly