Include inline emoji in JSON export

[Tyrrrz]

Closes #1026

• Adds messages[].inlineEmojis[] that contains an array of emoji objects, describing emoji used inside {message}.content.
• Adds messages[].embeds[].inlineEmojis[] that contains an array of emoji objects, describing emoji used inside {embed}.description.
• Both arrays are deduplicated and may be empty but never null.

[slatinsky]

Hello,

I have tested this pull requests and I have found some small issues:

1. messages[].embeds[].description sent by automod or by bots in a embed may contain custom emojis. Those emojis don't show up in messages[].inlineEmojis[]
2. the same emoji sent multiple times in the same messages[].content is not deduplicated.

Other than that, the pull request looks good to me. Including the name inlineEmojis

[Tyrrrz]

Hello,

I have tested this pull requests and I have found some small issues:

1. messages[].embeds[].description sent by automod or by bots in a embed may contain custom emojis. Those emojis don't show up in messages[].inlineEmojis[]
2. the same emoji sent multiple times in the same messages[].content is not deduplicated.

Other than that, the pull request looks good to me. Including the name inlineEmojis

Good points.

As for 1., do you think those emoji should be inside messages[].inlineEmojis[] or messages[].embeds[].inlineEmojis[]? The former is obviously easier, but I wonder if there's any downside.