login static method
Use to login to get the user information.
domain The IP or server's domain
acctID The datacenter's ID.
username The username to login
password The password of the user
@return The user's information
Implementation
static Future<LoginInfo> login(String domain, String acctID, String username, String password) async {
var p = LoginParam.builder()
.acctID(acctID)
.username(username)
.password(password)
.build();
return K3Client.getInstance()
.setDomain(domain)
.login(p);
}