Add Settings View

...lin/org/briarproject/briar/desktop/contact/ContactList.kt

...rproject/briar/desktop/conversation/ConversationScreen.kt

...arproject/briar/desktop/privategroups/PrivateGroupList.kt

...project/briar/desktop/settings/PlaceHolderSettingsView.kt

...org/briarproject/briar/desktop/settings/SettingDetails.kt

.../org/briarproject/briar/desktop/settings/SettingOption.kt

...briarproject/briar/desktop/settings/SettingsOptionList.kt

...org/briarproject/briar/desktop/settings/SettingsScreen.kt

.../briarproject/briar/desktop/settings/SettingsViewModel.kt

src/main/kotlin/org/briarproject/briar/desktop/ui/BriarUi.kt

...ain/kotlin/org/briarproject/briar/desktop/ui/Constants.kt

...in/kotlin/org/briarproject/briar/desktop/ui/MainScreen.kt

...g/briarproject/briar/desktop/viewmodel/ViewModelModule.kt

src/main/resources/strings/BriarDesktop.properties