Algorithmic constants and parameters for running optim within
  rrvglm are set using this function.
rrvglm.optim.control(Fnscale = 1, Maxit = 100,
                     Switch.optimizer = 3, Abstol = -Inf,
                     Reltol = sqrt(.Machine$double.eps), ...)Passed into optim as fnscale.
Passed into optim as maxit.
Iteration number when the "Nelder-Mead" method
  of optim is switched to the quasi-Newton "BFGS" method.
  Assigning Switch.optimizer a negative number
  means always BFGS, while assigning Switch.optimizer a value
  greater than maxits means always use Nelder-Mead.
Passed into optim as abstol.
Passed into optim as reltol.
Ignored.
A list with components equal to the arguments.
See optim for more details.