Fixed repeated request for create first account when all the accounts where removed after the app was left in an actitivy not root in its task
PreviewImageActivity protected against access to non-existing account
PreviewVideoActivity protected against access to non-exiting account
Fixed bad transitions after adding protection for removed accounts to PreviewVideoActivity
Merge remote-tracking branch 'origin/develop' into check_account_existance_in_gallery
UploadFileActivity protected agains access to non-existing account
ConflictsResolveActivity protected against access to non-existing account
Merge branch 'develop' into check_account_existance_in_gallery
Fixed lost of state of list of files in orientation changes
FIXED: right screen when the app is left in a video, the account is deleted, the orientation is changed, the app is opened and the account reloged-in
Merge branch 'develop' into check_account_existance_in_gallery
Merge pull request #204 from owncloud/check_account_existance_in_gallery

Check account existance when entering in the app through an activity showing preview or details of a file.