hardhat 1.0.0

• Recipe preprocessors now ignore non-standard recipe roles (i.e. not
  "outcome" or "predictor") by default when calling forge(). Previously,
  it was assumed that all non-standard role columns present in the original
  training data were also required in the test data when forge() is called.
  It seems to be more often the case that those columns are actually not
  required to bake() new data, and often won't even be present when making
  predictions on new data. For example, a custom "case_weights" role might be
  required for computing case-weighted estimates at prep() time, but won't
  be necessary at bake() time (since the estimates have already been
  pre-computed and stored). To account for the case when you do require a
  specific non-standard role to be present at bake() time,
  default_recipe_blueprint() has gained a new argument,
  bake_dependent_roles, which can be set to a character vector of
  non-standard roles that are required.

• New weighted_table() for generating a weighted contingency table, similar to
  table() (#191).

• New experimental family of functions for working with case weights. In
  particular, frequency_weights() and importance_weights() (#190).

• use_modeling_files() and create_modeling_package() no longer open the
  package documentation file in the current RStudio session (#192).

• rlang >=1.0.2 and vctrs >=0.4.1 are now required.

• Bumped required R version to >= 3.4.0 to reflect tidyverse standards.