Too much tuple

Primarily cleanup in IP network support.

• A bug in mask generation was fixed.
• libswoc can now be built on github.
• Internally IPSpace now uses a structure instead of a tuple. It was becoming increasing difficult to update the API as needed with a tuple.

One of the reasons for the change from a tuple is a compiler issue I was unable to track down where an IPSpace iterator would not iterate at run time in release mode. I suspect it was a bad optimization by the compiler with regard to reference values. Building release with symbols caused the problem to disappear making it almost impossible to usefully run a debugger on the problem. Of course everything worked in debug mode. Even adding some instrumentation code to detect the failure "fixed" the problem.