Add more events to the Plugin API

[vyPal]

Description

This PR aims to add support for various Bukkit inspired events to the Pumpkin Plugin API.

Events being added:

Player events:

• ChangeWorld - called when a player teleports to another world
• GamemodeChange - called when a player's game mode is changed
• Login - called while a player is joining but before they are added to the world
• Chat - when a player sends a chat message
• CommandSend - when a player executes a command
• Move - when a player moves
• Teleport - when a player is teleported

Server events:

• Broadcast - when a message is broadcast server-wide
• PluginEnable - when a plugin is enabled
• PluginDisable - when a plugin is disabled
• Command - when a command is executed by either console or RCON

Testing

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