Redirect all users if active room was renamed

Setting: Layout Sidenav Footer

Adds API_Gitlab_URL setting and overwrites Gitlab.Server

Fixed security issue -- non-admins able to delete channels https://github.com/RocketChat/Rocket.Chat/issues/564

initial implementation of oauth2 client support for gitlab server flow  #512

Load missed messages from opened rooms when reconnect

add links to deployment instructions for users without docker - closes #541

Prevent download of images in phone and allow click to download

Fix image stretching

Suggested by @rodrigok.

Looks much better on small images to be aligned in the center.  Especially if height needs to remain at 200px;

This way area doesn't expand after the image loads causing content to shift.

Fix search not coming up

Add Google Play button for app