patch: minor bugfix in cryptutil.py

[Ryan Barrett]

hi all. i've attached a patch that fixes a minor bug in the python openid 
library, in cryptutil.py. the patch is against 2.0.0-rc3b.

specifically, cryptutil has a code path that tries a few different sources of 
randomness in succession. one of them expects an OSError if a file() call 
fails, but file() throws IOError, not OSError. we're trying out the python 
openid library in a chroot, so this bit us.

-Ryan

p.s. out of curiosity, why are comments on openidenabled.com disabled?

--
http://snarfed.org/