With Jami-Daemon >= 14.0.0, the client doesn't need to construct
itself the history. This part is now handled by the daemon.
This patch uses the new API:
+ loadConversationMessages->loadConversation
+ SwarmMessageReceived/SwarmMessageUpdated/ReactionAdded/ReactionRemoved
+ remove MessageReceived
+ ConversationLoaded->SwarmLoaded

+ No need to use loadConversationUntil, the daemon will load whatever
the client needs.
+ No need to clear cache, just reset the body and emit data changes

Everything should work like before (even re-translation & changing
preview preference)

Change-Id: Iaf1fa3e84e8e157ae2d0bec210977f9a34415ebc