* Nolan ("tail.pdf") and other places mention *asymptotic* formulae
  --> use these for large |x|, notably for  dstable(*, log = TRUE)

* pstable() should also get   lower.tail = TRUE,  log.p = FALSE
  ~~~~~~~   arguments
* qstable() ditto

* using  doExtras to *not* run some tests when  --as-cran ,  as

     From: Prof Brian Ripley <ripley@stats.ox.ac.uk>
     Subject: Re: New version of copula uploaded 0.99-2
     Date: Tue, 29 May 2012 17:17:05 +0100

     ..  but the test times

     * checking tests ...  [173s/174s] OK
	Running doRUnit.R  [82s/83s]
	Running dstab-ex.R [34s/34s]
	Running pstab-ex.R [19s/19s]
	Running tails.R    [39s/39s]

     are more than we would like, so please consider reducing substantially
     next time around
     ...
