Add authentification support for password protected podcasts

Conflicts:
	res/values-cs/strings.xml
	res/values-de/strings.xml
	res/values-es/strings.xml
	res/values-fr/strings.xml
	res/values/strings.xml
	src/net/alliknow/podcatcher/EpisodeListActivity.java
	src/net/alliknow/podcatcher/PodcastActivity.java
	src/net/alliknow/podcatcher/Podcatcher.java
	src/net/alliknow/podcatcher/model/tasks/StorePodcastListTask.java
	src/net/alliknow/podcatcher/model/tasks/remote/LoadPodcastTask.java
	src/net/alliknow/podcatcher/services/PlayEpisodeService.java