Implement support for 2fa (Closes #74)

[ivanhrabcak]

I have tried to design the API so that existing code and control flow is not broken by this change.

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If 2fa is not set up, this basic example will work as expected:

from edupage_api import Edupage

edupage = Edupage()

try:
    edupage.login("Username", "Password", "Your school's subdomain")
except BadCredentialsException:
    print("Wrong username or password!")
except LoginDataParsingException:
    print("Try again or open an issue!")

You have successfully logged in.

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If 2fa is set up, you can login in a similar way — note the second_factor variable:

from edupage_api import Edupage

edupage = Edupage()

try:
    second_factor = edupage.login("Username", "Password", "Your school's subdomain")
    # or
    second_factor = edupage.login_auto("Username", "Password")
except BadCredentialsException:
    print("Wrong username or password!")
except LoginDataParsingException:
    print("Try again or open an issue!")

This will return the TwoFactorLogin object, which can be used to complete the login, or to resend the 2fa notification.

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There are two ways to complete the login process:

By confirming through the mobile application:

while not second_factor.is_confirmed():
    time.sleep(0.5)

second_factor.finish()

# You are now logged in!

By confirming the code (from email or mobile app):

second_factor.finish_with_code("123456")

# You are now logged in!