Added active status to static players list

[TK05]

Requested by #11

Added a boolean value to the static players list to represent their active status. Added get_active_players() and get_inactive_players() to make use of this new data.

Also updated data.md, examples.md and players.md to reflect these changes.

[TK05]

Also made a tool to update static player data 0251d16

Unfortunately it uses Selenium which isn't so great. I couldn't get the requests_html library to work for whatever reason. If anyone knows if there's an endpoint that could generate this data, feel free to let me know and I'll use that instead.

Basically right now it just scrapes https://stats.nba.com/players/list/.

[swar]

Active Players: https://stats.nba.com/stats/commonallplayers?IsOnlyCurrentSeason=1&LeagueID=00&Season=2018-19

All Players: https://stats.nba.com/stats/commonallplayers?IsOnlyCurrentSeason=0&LeagueID=00&Season=2018-19