add_method: Add a method to a dsc.
In stephens999/dscr: Dynamic Statistical Comparisons in R

Adds a method to a dsc

1 2	add_method(dsc, name, fn, args = NULL, outputtype = "default_output", gold_flag = FALSE)

`dsc`	The dsc to add the method to.
`name`	a character string name for the method
`fn`	a wrapper function that implements the method
`args`	a list of additional arguments to fn
`outputtype`	a string to indicate what type of output
`gold_flag`	a flag to indicate if the method is a "gold" method (which gets passed meta data as well as input data)