OC-3047: Hide the file size when the file is a folder
OC-3049: Remove the database update for the folder size data
Fix import in AccountUtilsTest
OC-3049: Remove the database update for the folder size data:  modify FileContentProvider and FileSyncAdapter.
Merge branch 'develop' into remove_folder_size_info
OC-3050: Grant the filelist doesn't refresh unnecessary because of the old update folder size
Merge pull request #414 from owncloud/remove_folder_size_info

Removed folder size from list of files, and folder size updates in database