Rework the Slack info command

[TimJentzsch]

Relevant issue: Closes #404

Description:

This is a complete rework of the info command in Slack, providing more data and formatting it in a more readable way.

Example output:

---

Info about u/Userson:

General:

• Gamma: 5 Γ (2 Γ in last 2 weeks)
• Joined on: 2020-04-21 (1.0 year ago)
• Last active: 2021-04-13 (1.1 weeks ago)

Transcription Quality:

• Checks: 2 (40.0% of transcriptions)
• Warnings: 1 (50.0% of checks)
• Watch status: Automatic (100.0%)

Debug Info:

• ID: 123
• Blacklisted: No
• Bot: No
• Accepted CoC: Yes

Checklist:

• Code Quality
• Pep-8
• Tests (if applicable)
• Success Criteria Met
• Inline Documentation
• Wiki Documentation (if applicable)