Moving some DataConnector related classes over to -api

[Rod Widdowson]

> My concern is just that I'm not sure it's any more correct to assume initialization in the constructor unless you're dealing
solely with
> classes that didn't have properties also. Maybe these didn't.

Well yes (they didn't).  

It's also important that :
 - The fact that they are Initializable is new 
-  We do not initialize in the no parameter constructors
-  I have left the constructors for classes that were already initializable alone (no initialize)

So I believe that from the outside the result is the same.

R