Pull up following revision(s) (requested by riastradh in ticket #1715):
share/man/man4/rnd.4: revision 1.26
share/man/man4/rnd.4: revision 1.27
share/man/man4/rnd.4: revision 1.28
share/man/man4/rnd.4: revision 1.25
Update man page to reflect switch from CTR_DRBG to Hash_DRBG.
Replace slightly wrong rant by shorter and slightly less long rant.
(If X and Y in Z/2Z are independent, then so are X and X+Y.  What was
I thinking.)
Update NIST SP800-90A reference.
New sentence, new line. Use \(em.

(bouyer)