- Add file_name field to `RealmEmoji` model and migration.
- Add emoji upload supporting to Upload backends.
- Add uploaded file processing to emoji views.
- Use emoji source url as based for display url.
- Change emoji form for image uploading.
- Fix back-end tests.
- Fix front-end tests.
- Add tests for emoji uploading.
Fixes#1134
Use `name_to_codepoint.json` file (and the similar structure in
emoji_codes.js) to map emoji names directly to codepoints and change
the rendered emoji image to `unicode/<codepoint.png>` rather than
`<emoji_name>.png`.
Fixes: #3539.
K.Kanakhin
Tim Abbott
Harshit Bansal