Merge pull request #641 from owncloud/thumbnails_for_downloaded_images

Thumbnails for downloaded images

diff --cc src/com/owncloud/android/datamodel/FileDataStorageManager.java
Simple merge

diff --cc src/com/owncloud/android/datamodel/OCFile.java
Simple merge

diff --cc src/com/owncloud/android/files/services/FileDownloader.java
Simple merge

diff --cc src/com/owncloud/android/providers/FileContentProvider.java
Simple merge