[NEW] REST API endpoints permissions.list and permissions.update. Deprecated endpoint permissions

[vynmera]

Closes #7961

This PR deprecates /api/v1/permissions in favor of a new /api/v1/permissions.list and adds /api/v1/permissions.update.

permissions.list

Practically the same as the old permissions, but the permissions are now in a permissions field and a success field is included.

Example response:

{
  "permissions": [
    {
      "_id": "access-permissions",
      "roles": [
        "admin"
      ],
      "_updatedAt": "2018-01-25T13:03:20.879Z",
      "meta": {
        "revision": 0,
        "created": 1516980515815,
        "version": 0
      },
      "$loki": 1
    },{
      ...
    }
  ],
  "success": true
}

permissions.update

Takes a single field permissions containing an array of objects, which contain the field _id and roles. These new permissions are then merged onto the previous.

Example request:

{
  "permissions": [
    {
      "_id": "access-permissions",
      "roles": ["admin"]
    }, {
      "_id": "clean-channel-history",
      "roles": ["admin", "owner"]
    }, {
      ...
    }
  ]
}

In this example, the access-permissions permission is changed to be granted to admins, and the clean-channel-history permission is changed to be granted to admins and channel owners.

The returned value is the same as that of permissions.list.

permissions deprecation

Since permissions directly returns an array, I have no clue how to implement a deprecation message properly. I've left it out for now, please do tell me if there is any way I could've handled it better.
Furthermore, the deprecation warnings I did add are targeted for 0.69.0, assuming my PR will be included in 0.66.0. If this is not the case, please change it or request me to change it.

[graywolf336]

@vynmera you don't have to keep merging develop into your branch, once we get ready to merge then we'll do it. :)

As far as deprecation notice, we have a helper method for that on the rest api: https://github.com/RocketChat/Rocket.Chat/blob/develop/packages/rocketchat-api/server/helpers/deprecationWarning.js

[vynmera]

@graywolf336 Aight :) If you need I can remake the branch.

I tried to use the deprecation notice, but there's a problem with the implementation of permissions.
permissions directly returns an Array (not an object), whereas deprecationWarning's parameter and return data is an object (it adds fields to the object you give it).
To implement that warning, we'd need to make a breaking change to the existing permissions, just to deprecate it.

[graywolf336]

@vynmera ahhhhhh okay, that makes sense. Then just duplicate that method's logging notice and update the docs.

As far as the branch, you can keep this one. :) Since we'll squash merge this pull request so there is only one commit for it.

[vynmera]

@graywolf336 Done! The docs update should already be in this PR: https://github.com/RocketChat/docs/pull/777