Cancellable Game Data RPC message Events

[kantesilvestrs]

Description

• Implements cancel evet flag for GameData and GameDataTo client RPC message flags, which can be triggered via CancelEvent action.
• Implements ICancellableEvent which exposes Action<bool> CancelEvent on events
• Implements ICancellableEvent on IPlayerChatEvent

Closes issues

• closes Plugin Event Prevent Default #257
• closes Add event cancelling to chat messages #92

[Alexejhero]

Add these to the closes list as well

• closes Add event cancelling to chat messages #92
• closes Pre and post events; Cancellation API #135
• closes Add pre/post events and event cancellation #145

[kantesilvestrs]

@AlexejheroYTB I added #92, but the other ones are not really covered by this PR's scope

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[realfaceitkantesilvestrs]

Why does #327 closes this PR @js6pak ?

[js6pak]

Because it implemented a way to cancel rpcs and cancellable chat messages.