Move CreateEntityListener to the EntityManager.

Small note for the future, we should probably look into condensing the
initialization of EntityManager... it's spread across three different
functions.
Add DESTROY_ENTITY event for despawning.
Normalize event listeners in GameMode.

Change to a model that I'm already using... it might be slightly more
maintainable... maybe. You can change it back if you want.
Update member/function documentation.

Use /** */ instead of /* */ so that documentation software can recognize
function documentation... it's better that way.
Add Tick event.

Change how EventType documentation is formatted.

This will make it work much better with documentation software.

Why do this? Because documentation can be helpful... also it's beautiful.
Add options parsing to the flocking behaviour.

Making strides towards component delta integration... An ambiguous way of
saying that I'm making groups move together based on individual cloud
movements.
Convert SOAR_ENTITY payload to use GameEnitityId.

Rather than int... it makes mores sense and is more portable. This
probably needs to happen with other events as well.
Add the tick event.

Add position updating to the Flocking behaviour.
Make Vector Map more generic as a Grid.

Use C++ templates to make a generic 2D array datastructure that isn't
horribly inefficient. (Though admittedly not extremely flexible.)
Add POSITIONAL_QUERY event.

Also fix the name of mCreateEntiityListener.

The query may be a bad idea since it increases coupling through the event
system, but I'm kinda out of ideas at this point. Open to suggestions for
an alternative.
Add Soaring and Flocking to the list of active Behaviours.

Also create entities to take advantage of them.

(Note: still in testing)
[Broken] Add clustering algorithm for grouping clouds.

For some reason, templates are not playing well with me. I'm going to need
some fresh eyes for this one. Help appreciated.