Use ranged for
Rename ccharactervector -> TccharacterVector
Hide implementation of CharacterContainer
Rename CharacterContainer::{findID -> find}
Use unordered_map in CharacterContainer

Using a hash map guarantees character look-up via ID in O(1).
This will be especially helpful when characters are exported
to Lua via ID only.
Also container content is now exposed via the for_each members,
accepting either a fitting lambda or member function.