facet_plot_fcn: Multiple partial dependency plots on one page
In breather/brightbox: Peek into any blackbox learner (including ensembles)

It can be helpful to view multiple partial dependency plots at once to get a sense of variable importance, relationships between variables, etc.

1 2	facet_plot_fcn(pd_list, plot_fcn = plot_partial_dependency, nrow = NULL, ncol = NULL, scales = "free")

`pd_list`	output from `loop_calculate_partial_dependency`
`plot_fcn`	a function that accepts the output from `calculate_partial_dependency` and returns a ggplot object. This function will be looped over `pd_list`.
`nrow`	int. Number of rows in layout
`ncol`	int. Number of columns in layout
`scales`	one of "`fixed`", "`free`", "`free_x`", "`free_y`". See `ggplot2::facet_wrap` for more information