nflfastR 5.1.0

• The function calculate_standings() has been deprecated. Please use nflseedR::nfl_standings() in nflseedR v2.0 instead. (#510)
• nflfastR now requires R 4.1 to allow the package to use R's native pipe |> operator. This follows the Tidyverse R version support rules. (#511)
• Fixed a bug where calculate_stats() incorrectly counted receiving_air_yards. (#500)
• Fixed a bug where vegas_wp variables were broken when spread_line data was missing. (#503)
• Fixed a bug where calculate_stats() incorrectly calculated target_share and air_yards_share when summary_level = "season". (#505)
• Fixed a bug where calculate_stats() incorrectly counted fumbles. (#514)
• Compatibility improvements with xgboost. (#517)

Thank you to @ak47twq, @isaactpetersen, @jacobakaye, @johnpholden, @marvin3FF, @mrcaseb, and @tanho63 for their questions, feedback, and contributions towards this release.