Add typing for api

[shenjackyuanjie]

add typing for auth.py add

    def __init__(self, ip_address: str, port: int, 
                 username: str, password: str, 
                 secure=False, cert_verify=False, 
                 dsm_version=7, debug=True, otp_code: str = None):

for most api add return type hint for filestation

and remove unessary super(xxx, self)

[shenjackyuanjie]

I think that's all for me to do other typing hint need more further reading the code sorry, I don't have many time

back to school!

[N4S4]

Typing added from PR #121