review identifier naming scheme

[cbernet]

good to keep the identifier as an integer, we don't want a class for that.

But then the class that manages the identifier is not an Indentifier.
Also, confusion with the index and the unique id.

Need to come up with names for:

• the Identifier class
• the identifier integer
• the index
• the unique id, which might denote either the whole identifier integer or the type + subtype + index...

[alicerobson]

Current proposal
IdCoder = the Identifier class
Identifier = the identifier integer
Index = the index
UniqueId = the unique id, for the type + subtype + index...

[cbernet]

perfect.

[cbernet]

Done.