Implement GA events

[trongthanh]

Adding GA tracking events with:

• Page view; When user go to a room or go to Home page
• Event; cat Host; create new room
• Event; cat Navigation; Switch tab
• Event; cat Playlist; book an existing song
• Event; cat Playlist; book song with URL (params: which origin)
• Event; cat Playlist; user player start playing a song (by click)
• Event; cat Playlist; user player stop playing a song (by click)
• Event; cat Host; assign host
• Event; cat Host; set new Naucoin value

Library to use: react-ga