Tags (Tricks) system

[gdude2002]

This will replace K9's tricks system once implemented. The idea is to have something similar, with the following design:

• Tags will be stored on Git only, and the bot will maintain a local copy of the repo
• As tags should be able to generate embeds, we've come up with a simple format: Markdown with YAML front matter. This won't actually be front matter in the strictest sense - it'll contain everything about the tag aside from the actual main content itself, including embed fields and colours.
• Add some additional parsing - for example, {Role:MODERATORS} to insert a role mention.
• Multiple tag types - text, embed and alias

This will involve writing some library-style code, but it should be possible to write a tag linter into the bot as well, so that the JAR could be downloaded by the CI system and used to lint the tags in the repo. We'll see, though.

[Scotsguy]

Done in #18 and FabricMC/community#2 🦞