Make both program arguments optional

[Vexatos]

It should be optional to enter the email address and password as program arguments. If the password is not entered, it should ask for the password in the next line, similar to other programs. If both aren't, it's ask for email address and password in that order. If possible, make the password input not print anything to terminal like it should be.

[RX14]

I'll make this a config file for now, have a first-time setup thingy later.