Some Post-demo Cleanups (#200)

* Remove redundant string

* Use placeholder avatar on home screen

* Add initial home screen ui test

* Fix settings screen PR remarks

* Remove UIKit alert from home screen sign out

* Remove UIKit alert from soft logout clear all data

* Add reference screenshots for home screen UI tests

* Formatting fixes

* Add clearing room method to client proxy

* Clear room proxies on screen dismiss

* Fix retain cycle in room view model

* Do not go into authentication state immediately

* Define sizes for user and room avatars on different screens

* Use defined avatar sizes everywhere

* Disable image disk caching

* Rename rounded corner shape

* Fix text color of placeholder avatars

* Fix PR reviews on formatted body text

* Fix merge conflict

* Remove shouldShowSenderDetails everywhere and just use it from inGroupState

* Remove redundant linter disablings

* Fix PR remarks

* Rename media provider size parameter

ElementX/Sources/Services/Room/RoomProxy.swift

@@ -42,7 +42,7 @@ class RoomProxy: RoomProxyProtocol {
     }()
     
     deinit {
-        #warning("Should any timeline listeners be removed??")
+        room.removeTimeline()
     }
     
     init(slidingSyncRoom: SlidingSyncRoomProtocol,

ElementX/Sources/Services/Room/RoomSummary/MockRoomSummaryProvider.swift

@@ -32,7 +32,7 @@ class MockRoomSummaryProvider: RoomSummaryProviderProtocol {
         RoomSummary(id: "2",
                     name: "Second room",
                     isDirect: true,
-                    avatarURLString: "mockImageURLString",
+                    avatarURLString: nil,
                     lastMessage: nil,
                     lastMessageTimestamp: nil,
                     unreadNotificationCount: 1),