Create ImageViewerActivity
Start ImageViewerActivity when image gets selected
Image pager
Show image metadata in ImageViewerActivity title
Mark SearchResult as having reached the last page
Infinite scrolling in ImageViewerActivity
Add TouchImageView
Multi-touch image zoom and pan
Share button
Download image action bar item
View on Web and View on Pixiv action items
Set image as wallpaper
Placeholder background for unfetched thumbnails
Auto-hide action bar
Keep the screen on while in ImageViewerActivity
Tag list dialog