Recreate new variations of existing functions with the suffix "times"

[uriahf]

• probs and reals should be identical to the input in conventional rtichoke functions

• fixed_times takes a vector as an input that always includes 0 and at least one additional fixed_time_points.

• times is a list with the same structure as probs and reals. for events (reals = 1) times must be in the range of fixed_times vector, for nonevents times must be higher than all relevant fixed_time_points or missing.

• [ ] prepare_performance_data() to prepare_performance_data_times()

Should include time_horizon as an additional column. Should include cumulative_incidence as an additional column.

• [ ] render_performance_table() to render_performance_table_times()

• Should accept only performance_data that includes time_horizon and cumulative incidence columns.

• [ ] create_performance_data() to create_performance_data_times()

• Includes both render_performance_table() and create_performance_data() in one step.