[Thread loading time improvements] When opening a thread, first show whatever there is in the cache/database and only afterwards request new posts

[K1rakishou]

Right now we wait until we got posts from the server, stored them into the database and then parsed them. This may take dozens of seconds when opening huge threads (1000+ posts) on slow devices. This will probably break "scroll to the last seen post" and "scroll to new posts" functions.