Added a dire sounding note about how crypto is required to build the

Added a dire sounding note about how crypto is required to build the
system.  Well, not really required if you know what you are doing, but
there's enough people that don't fit into this class that are getting
burned now that we need to say it is required.  The actual message
says that one should treat it as if it was required to try to be
weasilly for the nitpickers amoung us :-)Killed by signal 2.