+ add gift models emoji

GET /emoji/:gift - get customEmojiId mapping for a specific gift

~ add emoji field

GET /gift/:gift - detailed info about a certain gift

Since Bot API has recently allowed usage of custom emoji IDs for every bot, we've updated our API to contain custom emoji IDs for both model emojis and original emojis.

If you have any problems with the newly-added custom emoji IDs (for example, missing model emoji, or incorrect custom emoji ID for a model), please tell us about them in the comments. Thanks!