0.2: added parnames, parnames<-
minor fix to allow "profiles" of 1-parameter models
  (skip fdHess call)
minor change to print method for mle results
tweaking "vecpar" (to allow parameter vectors in objective function)
removed fdHess/nlme dependency

0.3: enhanced anova method, works with print.anova
tweaked namedrop() code -- ??

0.4 change AIC to AICc for corrections
    add AICtab for weights, delta, sort ... options

    expose error messages occuring within profile()
    uniroot tries harder to find a valid endpoint
    truncate terms in anova.mle at 80 characters

0.5 fix AICc bug!  (was deviance+2*k*(k+1)/(n-k-1), not AIC+2*k*(k+1)/(n-k-1)

0.6 add experimental formula interface
    change all names from mle to mle2 to avoid confusion/conflicts
       with stats4 version of mle
    change internal structure of data evaluation
    worked on vignette
    added optimizer slot (stub)

0.7 better df extraction in ICtab
    minor bug fix for AICc (allows AICc of nls objects)
    handle models with -1 in formula better:
	starting values set "all equal"
    made ANOVA formula line-length accessible
    added skip.hessian and trace arguments to mle2
    messed around with BIC definition -- attempt at consistency with nlme
    added rudimentary support for nlminb, constrOptim
    nlme now required for fdHess (which is required for
	nlminb since it doesn't compute a finite-diff
	Hessian)