Add send reply mode in RoomInputToolbarView in order to update text input placeholder when sending a reply.

Riot/Modules/Room/Views/InputToolbar/RoomInputToolbarView.h

@@ -69,6 +69,11 @@
  */
 @property (nonatomic) BOOL isEncryptionEnabled;
 
+/**
+ Tell whether the input text will be a reply to a message.
+ */
+@property (nonatomic, getter=isReplyToEnabled) BOOL replyToEnabled;
+
 /**
  Tell whether a call is active.
  */