Merge tag '0.5.1' into develop

0.5.1
add first implement rpc
fix gulpfile.js and package.json
fix oni mock
add public/animations.json public/suika.json
upd pixi to 2.1.0
fix js/ for new pixi
mv css/game.styl -> js/game.styl
fix main.go
add stats fps/ms
add hpbar to js/
add hpbar to State msg
upd public/main.js
fix js/gameobject.js
fix some jshint errors
upd public/main.js
add sounds (using howler)
upd public/main.js
fix README.md
Merge branch 'release/0.6.0'