v0.6.2 CRAN release

jskm 0.6.2

• Fix: Gray's test p-value was incorrect when using status.cmprsk with factor status variable. cmprsk::cuminc() was called without cencode, causing the first factor level (censoring) to be treated as an event. Now correctly sets cencode to the first factor level and returns the p-value for the specified status.cmprsk event type.