-----
Modify mcmcsamp to return the deviance in the sample only when the
optional argument 'deviance' is TRUE (default FALSE).
-----
Replace the use of the unexported replacement function LMEoptimize<-
in lmer.R by the function LMEopt, which always returns NULL but
(in contradiction to the language specification) modifies its first argument.
-----
Modify the one-argument form of the anova method for lmer objects (yet
  again) to calculate the F ratios.  It is the df, not the ratio that
  is controversial.
Should there be an extractor function for the mean square error?  If
  so, what should it be called?
-----
Determine what a "coef" function should do for multiple, possibly
  non-nested, grouping  factors.
-----
- Revive the "lmer" and "glmer" classes.  Slots like "family" should
  be in "glmer" only.  Many methods for "lmer" can be simplified as,
  for example, they will always use the scale factor.

- Add a "pedigree" class and methods for it.  Allow a pedigree
  argument in lmer.

- document print(<mer>) including an example  print(<lmer>, corr = FALSE)

