CreateNewDropoutMechanism: A function which creates a DropOut Mechanism object
In dejaVu: Multiple Imputation for Recurrent Events

A function which creates a DropOut Mechanism object

CreateNewDropoutMechanism(
  type,
  text,
  cols.needed = vector("character"),
  GetDropTime,
  parameters = NULL
)

`type`	The type of mechanism (e.g. "MCAR" or "MNAR")
`text`	A short string describing the mechanism (only used for printing)
`cols.needed`	Which columns in the SingleSim$data data frame must be included for this drop out mechanism to work. This option could allow drop out mechanism which depend on covariates to be included.
`GetDropTime`	A function with two arguments event.times and data, the corresponding entries from the SingleSim object. This function should return a list of dropout times (if a subject does not dropout its dropout time should be their current censored.time (i.e. the study follow up time))
`parameters`	A list of named parameters for the mechanism (only used for printing) or NULL if none