GiNaC/ginac print.h basic.h basic.cpp registrar.h function.pl

[Christian Bauer]

Update of /home/cvs/GiNaC/ginac

Modified Files:
	print.h basic.h basic.cpp registrar.h function.pl 
Log Message:
- print_context::duplicate() wasn't virtual
- fixed static initialization order problem with the print_context registry
- print methods can use basic::print_dispatch<>() to re-enter the double
  dispatch mechanism to defer to superclass methods