Add email address validation to livechat offline messages

[WIP]Admin tests

Updated SlackBridge startup connection logic and refactored method/variable names

Updated startup connection logic and refactored method/variable names to clarify between Rocket and Slack

* [WIP] Igloczek styles cleanup (#5354)

* WIP: Styles architecture cleanup

* Fix build

* Move the reset to css on client

* moving some CSS from api.addAssets to api.addFiles

* moving more files to built time compilers

* Restoring clearfix

* moving more files to built time compilers

* moving more files to built time compilers

* move fontello to theme package

* Renaming files to preserve git history

* Renaming files to preserve git history

* using min to preserve history

* Fix lint

* organizing

* Renaming files to preserve git history

* Renaming files to preserve git history

* Fix lint

* Fix lint

* Renaming files to preserve git history

* Moving another less file to cue compiled at build time

* Fix lint

* Moving another less file to be compiled at build time

* adding some part of lesshat into temp mixings

* Put transitions back with some temp redundant mixing

* commenting out unused mixings

* removed unused mixings from lesshat

* Fix lint

Adds a separator between Cancel and Authorize OAuth 2 Client

add reset setting to packageValue button and fix unread badge color

Fix livechat visitor status by storing their username on room object

Fix livechat current chats screen

Livechat new layout

fix rtl main-content overlay

fix save changes button

- Use different collection name on DDP
- Fix date filter for different date formats

Save user gravatar on insert via admin

LingoHub based on develop

Sets default avatar after setting username for the first time

- Also show the visitor status on chat inquiries (when using guest pool routing method)
- And send to client only the opened inquiries to that agent