[UPSTREAM] add interface for adding/removing users from a room in android

[jaytat0]

RocketChat#1230

[Cool-fire]

@jaytat0 @GOVINDDIXIT I have implemented the kick user feature in rocket chat which is waiting for review. This may help you in implementation in Widechat. I too have the bare implementation of the add user feature but I didn't made any PR for that in Rocket.chat

PR: RocketChat#2028

[bizzbyster]

Divyanhsu is working on this.

[bizzbyster]

First do the wireframe using Figma -- Eric to set it up for you. Let's do this in Rocket.chat branding.

[Shailesh351]

Update: DONE

• Add API for invite and remove user in Kotlin SDK ([NEW] Add invite and kick endpoints RocketChat/Rocket.Chat.Kotlin.SDK#249)
• Permission Check for remove user (Show only when user have permission to remove)
• Add Remove User Feature
• Permission Check for invite user (Show only when user have permission to invite)
• Add invite user feature(Using spotlight)