Show appropriate marker for friendly garrison based on composition

[billw2012]

[Sparker95]

In fact it is fairly easy to do, since client already has composition data about friendly garrisons. Now, how we could do it: if there is a ground vehicle, set some armored marker; if there is an air vehicle, set some air marker; if there is none, leave it a basic infantry marker. What else? BI also have markers for multiple dots to make NATO-like markers indicating size of formations, but I don't think that we need it.