Create and grow CUtlVector in memory

[Mikusch]

There are two instances where we use plugin storage in favor of CUtlVectors.

1. CObjectTeleporter::m_teleportWhereName - There were issues with growing the CUtlVector on the entity, which lead to nasty crashes. Currently we use an Entity methodmap to store the data in the plugin.
2. CMissionPopulator::UpdateMissionDestroySentries - There were issues with creating a new CUtlVector in memory to pass to the IPopulationSpawner::Spawn function. Currently we use the m_justSpawnedVector populated by CTFBotSpawner::Spawn.

Ideally, we find a way to create, access, and modify these CUtlVectors directly.