0.20.0

• Ability to disable sending nickname and message via push notification
• Added back 'delete room' button - closes #2351
• Added block and hidden options that can be set by env vars
• Added description and protected flag to default roles
• Added zh-TW and zh-HK
• Allow markdown in attachment fields
• Avoid using SVG for Sandstorm
• CAS Plugin: refactored logging
• Closes #2178; Admin View Logs should auto-scroll to end
• Closes #2316; Send test mail will block the server
• Closes #780; Do not change the sweet alert size in small screens, change the upload-preview size
• Closes #800; Add loading before main page render and add Fast Render
• Do not print passwor in new LDAP log
• Do not reset permission's roles at startup - closes #2164
• Do not slugify room names at renaming - fixes #1571
• Enable username as template from LDAP and enable username sync
• Expose getAvatarUrlFromUsername function to server side
• Fix 'render' callback of MessageTypes
• Fix publish user_data under "spotlight"
• Fix root url on server side
• Fix show more users button
• Fixed errors saving room info in admin
• Improve WebRTC audio quality
• Improved sidebar overlay - should fix RocketChat/Rocket.Chat.Cordova#15
• Improved system messages style
• Message with types are not groupable by default
• Moving room name to the beginning of the push notifications msg
• Observe API embed setting and apply immediatly - fixes #1989
• Remove _emojione.import.less from server.coffee
• Remove native sound of notifications
• Remove newline from en.i18n.json
• Remove unused files and closes #801
• Support for pinned message notification
• Updated sweetalert
• Uses the setting for validating rooms renaming - closes #2297