Merge branch 'develop' of github.com:RocketChat/Rocket.Chat into develop

.sandstorm/rocket.chat-128.svg

.sandstorm/rocket.chat-150.svg

.sandstorm/sandstorm-pkgdef.capnp

.sandstorm/screenshot.png

.sandstorm/screenshot1.png

.sandstorm/screenshot2.png

.sandstorm/screenshot3.png

.sandstorm/screenshot4.png

client/notifications/notification.coffee

server/methods/getAvatarSuggestion.coffee

server/methods/getUsernameSuggestion.coffee

server/startup/avatar.coffee