Added per channel formats, Started redesigning and improving the API.

[BlitzOffline]

This is work in progress and there is still a lot more to be done. Also not very well tested.

Ok some more information now that this is starting to gain a shape:

If everything works out right, other plugins won't need to add this plugin as a dependency since I've exposed the necessary stuff in the ChatChatAPI class.

Stuff exposed in ChatChatAPI:

• The UserHolder (for getting and removing users)
• The HookManager (for registering new hooks)
• The ChannelTypeRegistry (for registering new channel types)
• The RuleManager (for registering custom rules - read under for more info)
• The MentionsManager (for registering custom mentions - read under for more info)
• The MiniPlaceholdersManager (for registering custom tags - read under for more information)

Also other plugins will be able to get the ChatChatAPI instance using Bukkit's ServiceManager. Example:``

final RegisteredServiceProvider<ChatChatAPI> rsp = Bukkit.getServicesManager().getRegistration(ChatChatAPI.class)
if (rsp == null) {
  // Handle ChatChat missing here!
}
final ChatChatAPI api = rsp.getProvider();

Added:

• The ChatChatAPI and all the managers it provides
• Channel and Personal mention events (instead of them being the same)
• FormatsHolders and GlobalFormatsHolders
• Mentions - plugins can register their own custom mentions now
• MiniPlaceholders - plugins can register their own custom minimessage tags now. ChatChat also has a way to make custom placeholders from a file called placeholders.yml
• Rules - rules that apply to public and/or private chats. Messages sent by users need to respect those rules
• Hooks - added a way to actually register hooks within ChatChat.

Closes #85
Closes #90
Closes #100
Closes #147