[sugar] Please review recent rainbow patches.

[Michael Stone]

Folks,

I've got a small flurry of rainbow patches (everything from
rainbow-0.7.19..HEAD in http://dev.laptop.org/git/users/mstone/security)
that could use a bit of review. 

Many thanks,

Michael

P.S. - http://teach.laptop.org/~mstone/rainbow.rpm is an RPM containing
these patches. It's as yet untested, so I may well have broken things;
however, fixing that can happen in parallel with the review. :)

P.P.S. - I still haven't figured out how to really fix #8016 except by
excruciatingly dirty hacks. Any thoughts would be appreciated. :(