Bug fixes, UI improvements

• Fixes #542 inability to present correctly more than 256 tags
• Fixes #540 non-dismissing of search bar when returning to photo properties view
• Fixes #541 author name presented as "NSNotFound"
• Fixes deletion of smart albums after fetching albums in root
• Fixes non-update of photo selection after album content refresh
• Fixes management of association of tags to images
• Fixes refresh wheel not removed once first album data are received
• Fixes sending corrupted video files when sharing
• Fixes potential crash occurring when copying/moving photos to another album
• Fixes crash sometimes occurring when setting an album thumbnail