API scheme updated to layer 72.

Shortlog:
1. InputMediaUploadedDocument now has the new flag nosound_video;
2. InputMediaVenue now has the new string venue_type (it seems to be
   related to FourSquare Venue Types like "food/icecream" or another.
   See core.telegram.org/bot/api#Venue for details);
3. Add live locations (InputMediaGeoLive);
4. channelFull object now has a flag hidden_prehistory (see issue #113
   for details);
5. messageMediaVenue now has the same string venue_type;
6. messageMediaGeoLive now has the same fields as InputMediaGeoLive;
7. Add mysterious messageActionCustomAction;
8. Add messages.messagesNotModified (seems it's related to seamless
   message counter decrement as in Telegram for Android since v 4.8);
9. Remove inputMessagesFilterPhotoVideoDocuments;
10. Add filters inputMessagesFilterGeo and inputMessagesFilterContact;
11. Add updateChannelAvailableMessages (seems it's a new kind of Update
    related to listening of channel only updates);
12. Add channels.channelParticipantsNotModified;
13. inputBotInlineMessageMediaGeo now has the period field (like new
    live locations);
14. botInlineMessageMediaGeo now has the same period field;
15. BotResults now has a users vector field;
16. messages.botCallbackAnswer now has a new native_ui flag (seems it's
    related to some new kind of notification. Right now bots could send you
    either the message box or the modeless notification which is appeared
    from top of chat viewport);
17. Add inputPaymentCredentials[Android|Apple]Pay for (possible) Android
    Pay / Apple Pay support;
18. Add channelAdminLogEventActionTogglePreHistoryHidden for toggling
    history for chat newcomers (see issue #113);
19. Add strange recentMeUrl[Unknown|User|Chat|ChatInvite|StickerSet].
    Seems it's related to "Saved Messages" functionality.
20. Add help.recentMeUrl method;
21. messages.getHistory now has an argument hash;
22. messages.editMessage now has the new flag stop_geo_live related to
    Live Locations;
23. messages.editInlineBotMesages now has the same new flag;
24. Add new method messages.readMentions(peer:InputPeer);
25. Add new method help.getRecentMeUrls(referer:string);
26. channels.getParticipants now has a new parameter hash;
27. Add new method chanels.deleteHistory (seems it's related to issue
    #112);
28. Add new method channels.togglePreHistoryHidden (see #113).

This commit is based on upstream commit telegramdesktop/tdesktop@bccd801 and related to #114.