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/Resources/Localizations/en.lproj/Untranslated.strings

@@ -21,8 +21,6 @@
 "session_verification_screen_emojis_title" = "Lets check if these";
 "session_verification_screen_emojis_message" = "Open Element on one of your other sessions to compare.";
 
-"home_screen_all_chats" = "All Chats";
-
 // MARK: - Authentication
 
 "authentication_login_title" = "Welcome back!";