Added SPLICE-AWHEN.
Added plusminus-interval.
Started bibliography.
Started reorganizing statistics, redid central moments.

- SSE removed, replaced by CENTRAL-M2, also added -M3, -M4, SKEWNESS,
  KURTOSIS

- removed the whole "conforming accumulator" business, should be
  selected manually
Now using bibtex2html instead of jabref.
Added tests for central sample moments, fixed bugs.
New macros for defining == methods.
Write pool2 methods for centered moments, with tests.
Re-enabled quantiles.
Fixed typo.
Forgot to export ensure-sorted-reals.
Re-enabled covariance.
Commented out test for demean.
Re-enabled a covariance test.
Added shift-interval.
Re-added ensure-sorted-vector.
Added x- and y-moments.
Added sample-covariance.
Added covariance and correlation.
Removed silent.