Initial klay stuff.

Clay.hoon doesn't work yet, haven't done subscriptions.

Should probably changes yakis to only reference yaki mugs rather than
yakis themselves - and have a blob map in the dome. Otherwise
subscriptions and merges will suck for large stuff.
Zuse compiles again, new model.
Add useful stuff
zuse compiles again...
Broken.
Merge branch 'master' into klay

Conflicts:
	urb/zod/arvo/zuse.hoon
Fix merge...
Can boot subs now!
Unix sync out.
Zuse compiles w/ some merge code.
Semi-working merges.
Fast-forward merges should work (untested)
Simple change
Functional neoclay
Fix referential transparency in %cu
Trivial fixes
Merge branch 'master' into klay

Conflicts:
	urb/urbit.pill
Fix referential transparency in %merg
Send original copy to merge
Almost working