Bug fixes and improvements.

* Bug fix: Notification center swipe gesture stops working. (niw#36)
* Update Japanese localization format. (niw#32)
* Update traditional Chinese localization.
* Add "About" panel.
* Internal beauty.

Minor updates.

 * Support macOS 10.14 Mojave.

Minor updates.

 * Support MacBook Pro (2018) (niw#23).
 * Internal beauty.

Minor updates.

 * Add section title for haptic feedback strength.
 * Update menu item label and translations.

Minor updates.

* Add a feature to hide the application icon in the menu bar.

Minor updates.

* Support software update.
* Internal beauty.

Bump version.

Bump version.

Bump version.

Bump version.