Allow users to select between old and new navigation layout / UI .

Old Layout:  Unread private messages are listed with red dot above servers.  Close-spaced with no previews.  All private messages are shown to right of server list unless you click one of those servers.  Top left button is default to friend list, which opens when you open server.  Swipe right to view member list in servers.
(This allows user to see both new private and server notifications at once when on default.)

New Layout: All private messages are shown in a separate tab only, and spread out due to showing content previews.  You always see channels for whatever server you last clicked to the right of server list.  No default button, and when you open discord it will show the last channel you were in, clearing notifications for that channel so you may miss things.  Can only view member list by clicking channel names.
(This moves red dots to bottom of screen; must change tab to see which servers or member messaged.)

Some may enjoy or get used to the new interface. The rest of us want the option to use the one that most suits us.  (We already have option to select which color themes we want. This should be optional, too.)