0.21.0.988 RC

- "View Strings" for built-in language as well for translators (requires access to at least one -raw translation).
- Fixed: Invalid rule applied when selecting first item. Affects: *Suffix strings
- Added strings needed for language switch pop-up. See https://translations.telegram.org/en/android_x/new
- Added json_ChatDemo: array of Scene objects in JSON format.

Scene fields
on_date: array of integer. Optional. Format: [DAY,MONTH,YEAR,HOUR,MINUTE]. Use -1 if field value is not important. If current date or/and time matches specified value, scene will be displayed instead of default ones. Example: [7,9] or [7,9,-1] or [7,9,-1,-1,-1,-1]: Scene will be displayed on 7th September of any year.
guide: When set to 1, this scene will be displayed to translators.
member: string or User. Represents other party name.
members: array of User. Represents all members in a group chat
_: array of Message
min_version: Integer. Optional. If app version is lower than specified value, scene will be ignored. Do not set unless required, reserved for future.
max_version: Integer. Optional. If app version is higher than specified value, scene will be ignored. Do not set unless required, reserved for future.
lang: Integer. Optional. When this field is set, all string are used as localization key suffixes. Do not use unless you know what you do. Example: lang=1, text=name then json_1_name's content will be used as text content. See https://t.me/tgx_android_translate/34.

User array format
[user_id (int), first_name (string), last_name (string, optional), avatar_remote_id (string, optional)]

Message fields
out: 1 means message is outgoing.
author: Integer. Represents user_id of an author.
text: String (text) or array in format [text, enable_markdown=1]. Optional. Represents text message or caption.
audio: Array, format: [duration (int), title (string), performer (string)]. Optional.
voice: Integer (duration) or Array, format: [duration (int)].
photo: String (query) or Array, format: [query (string), width (int, optional), height (int, optional)] format.
sticker: Array, format: [width (int), height (int), thumbnail_remote_id (string), sticker_remote_id (string), set_id (long, optional)]
left: Integer (user_id). Represents left or kicked member user identifier. Group scenes only.
ttl: Integer (seconds). Amount of seconds of the new self-destruct timer. 0 means self-destruct timer has been disabled.
created: String (group title). Represents group creation message.
after: Integer (seconds). Amount of seconds after the previous message (if any). Do not set if it's not important for the scene.
date: Integer (unix timestamp). Optional exact date for the message. Do not set if it's not important for the scene. Keep in mind that the date is not displayed for the very first message (which is below "Chat Preview")