Extending input handlers with numbers

1. Define an input handler for numeric data in the zzz.R file.

registerInputHandler(
  "OSUICode.textNumber", function(data, ...) {
    if (is.null(data)) {
      NULL
    } else {
      res <- as.numeric(unlist(data))
      if (is.na(res)) {
        data
      } else {
        res
      }
    }
  }, force = TRUE)