Emit Animation Events

[martindevans]

Support a timeline of events in animation clips, when the animation is played emit the event (via the normal Myre event system). This allows things like footstep noises to be specified in the animation XML file with the correct timestamp.

[martindevans]

This will require some careful thinking about how to pass this data into the event system. The events deserialized from the file will not be strongly typed (obviously).

• Refactor event system to expose an additional less strong interface e.g:

GetEvent(Type t).Send(Object data)

• Use reflection to interact with the strong interface we currently have.
• Generate code and compile it (at content build time) which interacts with the event system. Load this code into engine when content is loaded.

[martindevans]

The events in the content pipeline need some type. There are two options here:

• Load event types into the content pipeline, this is problematic as the events are likely within the engine and we don't really want to load that into the content pipeline
• Leave the type of events undefined until it's loaded at runtime, then we do XML deserialization into the correct type then and there (no type checking of content files :-1: )