Switch to keyboard handling

Signed-off-by: Igor Yeryomin <yeryomin.igor@gmail.com>
Add simple element centering

Signed-off-by: Igor Yeryomin <yeryomin.igor@gmail.com>
Add moving by element (reveal on element size)

Signed-off-by: Igor Yeryomin <yeryomin.igor@gmail.com>
Little fix move amount

Signed-off-by: Igor Yeryomin <yeryomin.igor@gmail.com>
Add dropping elements at the last positions

Signed-off-by: Igor Yeryomin <yeryomin.igor@gmail.com>
Example #1

Signed-off-by: Igor Yeryomin <yeryomin.igor@gmail.com>