rsample 0.0.7

Lower threshold for pooling strata to 10% (from 15%) (#149).
The print() methods for rsplit and val_split objects were adjusted to show "<Analysis/Assess/Total>" and <Training/Validation/Total>, respectively.
The drinks, attrition, and two_class_dat data sets were removed. They are in the modeldata package.
Compatability with dplyr 1.0.0.

`rsample` 0.0.6

Added validation_set() for making a single resample.
Correct the tidy method for bootstraps (#115).
Changes for upcoming `tibble release.
Exported constructors for rset and split objects (#40)
initial_time_split() and rolling_origin() now have a lag parameter that ensures that previous data are available so that lagged variables can be calculated. (#135, #136)

Added three functions to compute different bootstrap confidence intervals.
A new function (add_resample_id()) augments a data frame with columns for the resampling identifier.
Updated initial_split(), mc_cv(), vfold_cv(), bootstraps(), and group_vfold_cv() to use tidyselect on the stratification variable.
Updated initial_split(), mc_cv(), vfold_cv(), bootstraps() with new breaks parameter that specifies the number of bins to stratify by for a numeric stratification variable.

Small maintenence release.

Added function initial_time_split() for ordered initial sampling appropriate for time series data.

fill() has been renamed populate() to avoid a conflict with tidyr::fill().
Changed the R version requirement to be R >= 3.1 instead of 3.3.3.
The recipes-related prepper function was moved to the recipes package. This makes the rsample install footprint much smaller.
rsplit objects are shown differently inside of a tibble.
Moved from the broom package to the generics package.

initial_split, training, and testing were added to do training/testing splits prior to resampling.
Another resampling method, group_vfold_cv, was added.
caret2rsample and rsample2caret can convert rset objects to those used by caret::trainControl and vice-versa.
A function called form_pred can be used to determine the original names of the predictors in a formula or terms object.
A vignette and a function (prepper) were included to facilitate using the recipes with rsample.
A gather method was added for rset objects.
A labels method was added for rsplit objects. This can help identify which resample is being used even when the whole rset object is not available.
A variety of dplyr methods were added (e.g. filter, mutate, etc) that work without dropping classes or attributes of the rsample objects.

Initial public version on CRAN