cfbfastR 1.9.0

Added functions to access ESPN API:

• espn_cfb_calendar()
• espn_cfb_schedule()
• Added EPA and WPA processing to espn_cfb_pbp()
• espn_cfb_team_stats()

Added functions to pull data from the data repo:

• load_cfb_rosters()
• load_cfb_schedules()
• load_cfb_teams()

• Removes furrr, future dependencies, adds Rcpp, RcppParallel, and purrr dependencies