Prevented flagging of Tiles that have already been exploded. Removed a redundant explode() call
Split event bindings between desktop and touch-enabled mobile devices. Added short-touch support for flagging Tiles and long-touch support for checking Tiles.
Added CSS animations for explosions and modified some styles to soften look and feel.
Added support for an easy mode where clear tiles (0 surrounding mines), and their surrounding tiles are already exposed for the player. Moved some code into an init() function to facilitate this and future game resets.
Added support for resetting game upon lose/win status. Cleaned up some lines and added forgotten details on some inline comments.