reddit: update tuples.
twitter: Add home-timeline and home-timeline.
random: 40% faster random-bytes*.
math: fix docs for next-power-of-2 and some tests.
random: faster random-bits, make some things private.
random: some cleanup.
vocabs: faster child-vocab?.
sequences: faster head? and tail?.
xml.tokenize: fix cdata parsing problem.
hash-sets: faster members.
hashtables: slightly faster associate and collect-pairs.
random.mersenne-twister: fix non-random bias.
random.mersenne-twister: more complete fix for bias.