[chord] new auth type patch

[Michael Walfish]

| I don't understand why you want to cut chord at pdos out of the loop.  The

I did not want to cut anyone out of the loop. I perhaps incorrectly
assumed that others were not interested and that less traffic was better
than more traffic. I am sorry.

| only effect that will have is to remove the record of design discussions
| and leave it so that people will continue not to have any idea what is
| going on with the source code. 

I'm certainly not trying to achieve either of these objectives.

| also, regarding how to proceed, let's wait until benjie finishes
| the KEYHASH updates (to be "KEYHASH with salt"), and see how things
| look from there.  as I said before, i am inclined to take the code
| cleanup and noauth patches if they could be separated.  perhaps
| once benjie is done, it will be easy for you to produce these
| patches.

yes, benjie and I had been corresponding about that. I agree -- now that
he's committed his changes, it won't be hard to put the cleanup and noauth
stuff in there and to produce a separate patch. for the record, there
wasn't much cleanup and most of the refactoring becomes unecessary if
there's still only one block type that is public key-related.

Tomorrow I'll send around a patch to HEAD that contains the remainder of 
my hoped-for changes. (Benjie did most of it.)