Added standard column selection for Feed table
Added FeedPreferences class
Add feed preference to include/exclude certain feeds from auto downloads
Added tests for DBReader
Added settings and description label to FeedInfoActivity, improved layout
Merge branch 'feed_preferences' into develop

Conflicts:
	res/values/strings.xml
	src/de/danoeh/antennapod/storage/DBTasks.java
	src/de/danoeh/antennapod/storage/PodDBAdapter.java
Temporarily removed preference (again)

Might be re-added later.