Replace sqlite3 with postgresql

[Galarzaa90]

The idea is to replace sqlite3 with an implementation that supports asynchronous operations to avoid blocking the main loop and follow discord.py conventions.

Now that NabBot is open for the public to invite to their servers, a increase of the database is expected. A migration to postgresql is recommended.

However, compared to sqlite, postgresql is harder to install and mantain, increasing the difficulty on self-hosted NabBot instances. Not to mention this will be a completely breaking change.

Progress

Migration

• [x] Database access
• [x] Database schema
• [x] Data migration
  • [x] Characters
  • [x] Deaths
  • [x] Level ups
  • [x] Server settings
  • [x] Auto roles
  • [x] Joinable roles
  • [x] Events
  • [x] Watched List
  • [x] Ignored channels list
• [x] Character storage
• [x] Highscore storage
• [x] Tracking tasks
• [x] Prefixes
• [x] Cogs
  • [x] Admin cog
  • [x] Core cog
  • [x] General cog
  • [x] Info cog
  • [x] Mod cog
  • [x] Owner cog
  • [x] Roles cog
  • [x] Settings cog
  • [x] Tibia cog
  • [x] Tracking cog
• [x] Remove all sql references

Optimization and refactoring

• [ ] Cogs
  • [ ] Admin cog
  • [ ] Core cog
  • [ ] General cog
  • [ ] Info cog
  • [ ] Mod cog
  • [ ] Owner cog
  • [ ] Roles cog
  • [ ] Settings cog
  • [ ] Tibia cog
  • [ ] Tracking cog
  • [ ] Improve Watched lists
  • [ ] Improve Autoroles

New features

• [x] Command stats
• [ ] Character name history
• [ ] Character world history
• [ ] Character owner histroy 👀

[Galarzaa90]

This is being worked on branch feat-postgresql