Update maintainer

[kkmann]

@MatheMax Let's get {adoptr} back on CRAN! This PR at least passes R CMD CHECK again. Problem is that we now get more findings from CRAN x)

• Please omit the redundant "in R" at the end of your title.

• Please write references in the description of the DESCRIPTION file in the form authors (year) doi:... (If you want to add a title as well please put it in quotes: "Title") So please add authors and (year) as well.

• Please add \value to .Rd files regarding exported methods and explain the functions results in the documentation. Please write about the structure of the output (class) and also what the output means. (If a function does not return a value, please document that too, e.g.
  \value{No return value, called for side effects} or similar) Missing Rd-tags:
  boundary-designs.Rd: \value
  Constraints.Rd: \value
  critical-values.Rd: \value
  cumulative_distribution_function.Rd: \value
  get_initial_design.Rd: \value
  make_tunable.Rd: \value
  n.Rd: \value
  plot-TwoStageDesign-method.Rd: \value
  print.adoptrOptimizationResult.Rd: \value
  probability_density_function.Rd: \value
  Scores.Rd: \value
  tunable_parameters.Rd: \value

• decide how to handle "print.adoptrOptimizationResult.Rd: missing \value"

• \dontrun{} should only be used if the example really cannot be executed (e.g. because of missing additional software, missing API keys, ...) by the user. That's why wrapping examples in \dontrun{} adds the comment ("# Not run:") as a warning for the user. Does not seem necessary.
  Please replace \dontrun with \donttest.
  Please unwrap the examples if they are executable in < 5 sec, or replace dontrun{} with \donttest{}.
  -> minimize.Rd

• Please make sure that you do not change the user's options, par or working directory. If you really have to do so within functions, please ensure with an immediate call of on.exit() that the settings are reset when the function is exited.
  e.g.:
  ...
  oldpar <- par(no.readonly = TRUE) # code line i
  on.exit(par(oldpar)) # code line i + 1
  ...
  par(mfrow=c(2,2)) # somewhere after
  ...
  e.g.: -> R/TwoStageDesign.R
  If you're not familiar with the function, please check ?on.exit. This function makes it possible to restore options before exiting a function even if the function breaks. Therefore it needs to be called immediately after the option change within a function.

• Please always make sure to reset to user's options(), working directory or par() after you changed it in examples and vignettes and demos.
  e.g.: -> inst/doc/adoptr_jss.R
  old <- options(digits = 3)
  ...
  options(old)

• Please do not modify the global environment (e.g. by using <<-) in your functions. This is not allowed by the CRAN policies. -> tests/testthat/test_ContinuousPrior.R;
  tests/testthat/test_IntegralScores.R; tests/testthat/test_minimize.R; tests/testthat/test_tunable.R; tests/testthat/test_TwoStageDesign.R

• make sure that pkgdown site builds

[MatheMax]

Do we need the function "print.adoptrOptimizationResult"?

[MatheMax]

@kkmann Maybe "make sure that pkgdown site builds" is solved with d6f4888