release v1.6

[Core] Re-code core
[Added] New supported platform (Twitch.tv, Justin.tv)
[Added] Pull and display emoticons of current platform
[Added] Dynamic load GJTV icon list for in-place icon filtering
[Added] Icon sorting by default, usage and recent
[Added] Icon usage reset button
[Added] Local storage for icon usage, selected genre, latest mode of
dark mode and sorting
[Added] Icon filtering message
[Added] Iconset pixel, ghost, xmas, freeze, sick
[Improved] Emotify using method of current platform
[Improved] On-click enlarge to original size insteads of 100% width of
chatroom
[Improved] Trigger method of heavy features
[Improved] Google analytics event tracking
[Minor] Dark mode css