Calls the DispatchThink() game DLL function on an entity, triggering it to
think if applicable.
DispatchThink() checks the entity for the FL_DORMANT flag - if it is
set, the entity will not proceed to think. It will first call the
class-specific think function and eventually CBaseEntity::Think(), thus
triggering other think hooks and forwards.
This function has no return value.
If an invalid entity index is provided, an error will be