* All functionality is moved into namespace CGALi, in namespace CGAL
there remain forward functions for the geometric types from the CGAL
kernel thereby fully maintaining backwards compatibility; nothing
changes on the user level.
* In the CGALi part, all types are referred to as K::Type rather than
Type<K>.
* In the CGALi part, all functions have a kernel object as last
argument, not only to ease the matching (no explicit template
argument needed), but also to be able to handle kernels with state.