Future Enhancements

1. Rationalise naming and arguments to functions:
   1. Some Tcl interfaces don't take "-io handle" notation (quit_displays)
   2. We refer to "result" in function names, but "id" in arguments. They're the same.
2. Add more type conversion routines. Also rationalise the existing routines. We should have a completely orthoganal set of interrogation function so that manipulation contigs, types and ids are the same.
3. Document usage of registration scheme within the contig comparitor (it's not straight forward or immediately obvious).