MTLR 0.2.2

MTLR 0.2.1

Added the option to obtain survival probabilities at specified times (see predict with type = "prob_times").
When using predict with "prob_event" there is no longer a linear extension added if the survival curve never reaches 0. The linear extension is still present in the "mean_time" and "median_time" options however.
Internally some sapply commands were refactored so to not iterate over indexes.
Tests were changed as to not clash with future ggplot2 updates -- tests were checking against internal structures as opposed to visual differences.

Added an option to optimize concordance instead of the log-likelihood when selecting a value for C1 in mtlr_cv.
Removed ellipses from create_folds since it's easy to use type instead of foldtype when passing in arguments.
Fixed a bug where if all data was left or right censored an error was thrown since there was no interval censored data.
mtlr_cv output is not best_C1 and not bestC1 to match the documentation.
Removed usage of Rcpp data structures inside MTLRHelper.cpp. This was not needed and just wasting time when transferring them to armadillo structures.
A number of printing fixes were made, e.g. printing out all variable names at once instead of one at a time for warnings and actually printing results when verbose = T for mtlr_cv.
When biases are trained they now assume the data are uncensored.