Add face recognition authentication

[hsluoyz]

This can be done by Go (integrated into Casdoor) or Python (a standalone process, which communicates with Casdoor's Go code), both OK.

The input is the video stream from browser, the output the Casdoor user's ID (orgname/username). The facial data can be stored into Casdoor's user table in advance.

[casbin-bot]

@seriouszyx @ComradeProgrammer @Resulte